diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,40 @@
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to the [Haskell Package Versioning Policy](https://pvp.haskell.org/).
 
+## [1.1.0] - 2026-10-01
+
+### Added
+
+- `runMarionetteTWith`, allowing connections to an arbitrary host and port.
+- `ClientEnv`, the reader environment that `MarionetteT` runs against.
+- `Test.Marionette.Actions` and `Test.Marionette.Key` modules to support structured virtual input device actions.
+
+### Removed
+
+- `UnexpectedResult`, unexpected / timed out responses are now discarded rather than ending the session.
+- `CommandWithCallback`, replaced by `QueuedCommand`.
+
+### Changed
+
+- `incoming` takes a callback to run if reading or decoding the connection ever fails,
+  instead of asynchronously killing the whole session.
+- `MarionetteTimeout` carries the `Command` that timed out instead of the raw wire message.
+
+### Fixed
+
+- Command timeouts no longer close the session.
+- Raised command timeout from 5s to 15s.
+- Closed connection no longer spin the reader.
+- Command callback are before sending instead of after.
+- Timed-out commands are deregistered.
+- `Test.Marionette.Commands.performActions` now accepts action sequences to simulate keyboard, mouse, and touch events, rather than doing nothing.
+
+## [1.0.1] - 2026-08-07
+
+### Fixed
+
+- Rethrow async exceptions in the Client.
+
 ## [1.0.0] - 2026-07-14
 
 ### Added
diff --git a/marionette.cabal b/marionette.cabal
--- a/marionette.cabal
+++ b/marionette.cabal
@@ -1,6 +1,6 @@
 cabal-version: 3.0
 name: marionette
-version: 1.0.0
+version: 1.1.0
 category: Web
 synopsis: Marionette protocol for Firefox
 description:
@@ -77,7 +77,7 @@
     base64-bytestring >=1.2 && <1.3,
     binary >=0.8 && <0.9,
     binary-parsers >=0.2 && <0.3,
-    containers >=0.7 && <0.8,
+    containers >=0.7 && <0.9,
     exceptions >=0.10 && <0.11,
     hashable >=1.5 && <1.6,
     mtl >=2.3 && <2.4,
@@ -89,6 +89,7 @@
   exposed-modules:
     Test.Marionette
     Test.Marionette.AccessibilityProperties
+    Test.Marionette.Actions
     Test.Marionette.Class
     Test.Marionette.Client
     Test.Marionette.Commands
@@ -96,6 +97,7 @@
     Test.Marionette.Cookie
     Test.Marionette.Element
     Test.Marionette.Frame
+    Test.Marionette.Key
     Test.Marionette.Orientation
     Test.Marionette.Protocol
     Test.Marionette.Rect
@@ -112,11 +114,35 @@
   hs-source-dirs: test
   main-is: Main.hs
   build-depends:
+    directory >=1.3 && <1.4,
+    filepath >=1.5 && <1.6,
     hspec >=2.11 && <2.12,
     hspec-expectations-lifted >=0.10 && <0.11,
     http-types >=0.12 && <0.13,
     lucid2 >=0.0 && <0.1,
     marionette,
+    network >=3.2 && <3.3,
+    retry >=0.9 && <0.10,
+    temporary >=1.3 && <1.4,
     typed-process >=0.2 && <0.3,
     wai >=3.2 && <3.3,
     warp >=3.4 && <3.5,
+
+test-suite marionette-client-test
+  import: common
+  type: exitcode-stdio-1.0
+  ghc-options:
+    -threaded
+    -with-rtsopts=-N
+    -Wno-unused-packages
+
+  hs-source-dirs: test
+  main-is: ClientSpec.hs
+  build-depends:
+    binary >=0.8 && <0.9,
+    hspec >=2.11 && <2.12,
+    hspec-expectations-lifted >=0.10 && <0.11,
+    marionette,
+    network >=3.2 && <3.3,
+    network-simple >=0.4.5 && <0.5,
+    unliftio >=0.2 && <0.3,
diff --git a/src/Test/Marionette.hs b/src/Test/Marionette.hs
--- a/src/Test/Marionette.hs
+++ b/src/Test/Marionette.hs
@@ -66,7 +66,8 @@
 -- >   (elementClick =<< findElement (ById "primary-button"))
 -- >     `catchError` \_ -> elementClick =<< findElement (ById "fallback-button")
 module Test.Marionette
-    ( module Test.Marionette.Class
+    ( module Test.Marionette.Actions
+    , module Test.Marionette.Class
     , module Test.Marionette.Client
     , module Test.Marionette.Commands
     , module Test.Marionette.Cookie
@@ -84,8 +85,14 @@
     )
 where
 
+import Test.Marionette.Actions
 import Test.Marionette.Class (Marionette)
-import Test.Marionette.Client (MarionetteT, runMarionetteT)
+import Test.Marionette.Client
+    ( MarionetteT
+    , defaultCommandTimeout
+    , runMarionetteT
+    , runMarionetteTWith
+    )
 import Test.Marionette.Commands
 import Test.Marionette.Context (Context (..))
 import Test.Marionette.Cookie (Cookie (Cookie))
diff --git a/src/Test/Marionette/Actions.hs b/src/Test/Marionette/Actions.hs
new file mode 100644
--- /dev/null
+++ b/src/Test/Marionette/Actions.hs
@@ -0,0 +1,216 @@
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# OPTIONS_GHC -Wno-partial-fields #-}
+
+-- | The <W3C https://w3c.github.io/webdriver/#actions Actions> API.
+module Test.Marionette.Actions where
+
+import Data.Aeson (ToJSON (toJSON), Value (String), object, (.=))
+import Data.Text (Text)
+import Data.Text qualified as Text
+import Test.Marionette.Element (Element)
+import Test.Marionette.Key (Key)
+import Prelude
+
+-- | Where a pointer or wheel action is anchored.
+data Origin
+    = -- | The top-left of the viewport.
+      Viewport
+    | -- | The input source's current position.
+      Pointer
+    | -- | The centre of the given element.
+      FromElement Element
+    deriving stock (Show, Eq)
+
+instance ToJSON Origin where
+    toJSON Viewport = String "viewport"
+    toJSON Pointer = String "pointer"
+    toJSON (FromElement element) = toJSON element
+
+-- | Which mouse button an action addresses.
+data Button
+    = LeftButton
+    | MiddleButton
+    | RightButton
+    | BackButton
+    | ForwardButton
+    deriving stock (Show, Eq, Enum, Bounded)
+
+-- | The kind of physical device a pointer input source represents.
+data PointerType = Mouse | Pen | Touch
+    deriving stock (Show, Eq)
+
+instance ToJSON PointerType where
+    toJSON = String . Text.toLower . Text.show
+
+-- | One tick of a pointer input source's action list.
+data PointerAction
+    = -- | Do nothing for this many milliseconds, or until every other
+      -- source's action in this tick has finished, whichever is longer.
+      PointerPause {durationMs :: Int}
+    | -- | Move to (or by, relative to the 'Origin') the given position over
+      -- the given number of milliseconds.
+      PointerMove {durationMs :: Int, origin :: Origin, x :: Int, y :: Int}
+    | PointerDown Button
+    | PointerUp Button
+    deriving stock (Show, Eq)
+
+instance ToJSON PointerAction where
+    toJSON PointerPause{..} =
+        object
+            [ "type" .= String "pause"
+            , "duration" .= durationMs
+            ]
+    toJSON PointerMove{..} =
+        object
+            [ "type" .= String "pointerMove"
+            , "duration" .= durationMs
+            , "origin" .= origin
+            , "x" .= x
+            , "y" .= y
+            ]
+    toJSON (PointerDown button) =
+        object
+            [ "type" .= String "pointerDown"
+            , "button" .= fromEnum button
+            ]
+    toJSON (PointerUp button) =
+        object
+            [ "type" .= String "pointerUp"
+            , "button" .= fromEnum button
+            ]
+
+-- | One tick of a key input source's action list.
+data KeyAction
+    = KeyPause {durationMs :: Int}
+    | KeyDown Key
+    | KeyUp Key
+    deriving stock (Show, Eq)
+
+instance ToJSON KeyAction where
+    toJSON KeyPause{..} =
+        object
+            [ "type" .= String "pause"
+            , "duration" .= durationMs
+            ]
+    toJSON (KeyDown key) =
+        object
+            [ "type" .= String "keyDown"
+            , "value" .= key
+            ]
+    toJSON (KeyUp key) =
+        object
+            [ "type" .= String "keyUp"
+            , "value" .= key
+            ]
+
+-- | One tick of a wheel input source's action list.
+data WheelAction
+    = WheelPause {durationMs :: Int}
+    | -- | Scroll by the given @(deltaX, deltaY)@ pixels, anchored at the
+      -- given @(x, y)@ relative to the 'Origin', over the given number of
+      -- milliseconds.
+      Scroll
+        { durationMs :: Int
+        , origin :: Origin
+        , x :: Int
+        , y :: Int
+        , deltaX :: Int
+        , deltaY :: Int
+        }
+    deriving stock (Show, Eq)
+
+instance ToJSON WheelAction where
+    toJSON WheelPause{..} =
+        object
+            [ "type" .= String "pause"
+            , "duration" .= durationMs
+            ]
+    toJSON Scroll{..} =
+        object
+            [ "type" .= String "scroll"
+            , "duration" .= durationMs
+            , "origin" .= origin
+            , "x" .= x
+            , "y" .= y
+            , "deltaX" .= deltaX
+            , "deltaY" .= deltaY
+            ]
+
+-- | One tick of a "none" input source's action list.
+newtype NoneAction = NonePause {durationMs :: Int}
+    deriving stock (Show, Eq)
+
+instance ToJSON NoneAction where
+    toJSON NonePause{..} =
+        object
+            [ "type" .= String "pause"
+            , "duration" .= durationMs
+            ]
+
+-- | A virtual input device and the sequence of actions to dispatch on it.
+data InputSource
+    = PointerInput
+        { sourceId :: Text
+        , pointerType :: PointerType
+        , pointerActions :: [PointerAction]
+        }
+    | KeyInput
+        { sourceId :: Text
+        , keyActions :: [KeyAction]
+        }
+    | WheelInput
+        { sourceId :: Text
+        , wheelActions :: [WheelAction]
+        }
+    | NoneInput
+        { sourceId :: Text
+        , noneActions :: [NoneAction]
+        }
+    deriving stock (Show, Eq)
+
+instance ToJSON InputSource where
+    toJSON PointerInput{..} =
+        object
+            [ "type" .= String "pointer"
+            , "id" .= sourceId
+            , "parameters" .= object ["pointerType" .= pointerType]
+            , "actions" .= pointerActions
+            ]
+    toJSON KeyInput{..} =
+        object
+            [ "type" .= String "key"
+            , "id" .= sourceId
+            , "actions" .= keyActions
+            ]
+    toJSON WheelInput{..} =
+        object
+            [ "type" .= String "wheel"
+            , "id" .= sourceId
+            , "actions" .= wheelActions
+            ]
+    toJSON NoneInput{..} =
+        object
+            [ "type" .= String "none"
+            , "id" .= sourceId
+            , "actions" .= noneActions
+            ]
+
+-- | A single mouse pointer input source named @"mouse"@.
+mouse :: [PointerAction] -> InputSource
+mouse = PointerInput "mouse" Mouse
+
+-- | A single pen pointer input source named @"pen"@.
+pen :: [PointerAction] -> InputSource
+pen = PointerInput "pen" Pen
+
+-- | A single touch pointer input source named @"touch"@.
+touch :: [PointerAction] -> InputSource
+touch = PointerInput "touch" Touch
+
+-- | A single keyboard input source named @"keyboard"@.
+keyboard :: [KeyAction] -> InputSource
+keyboard = KeyInput "keyboard"
+
+-- | A single wheel input source named @"wheel"@.
+wheel :: [WheelAction] -> InputSource
+wheel = WheelInput "wheel"
diff --git a/src/Test/Marionette/Client.hs b/src/Test/Marionette/Client.hs
--- a/src/Test/Marionette/Client.hs
+++ b/src/Test/Marionette/Client.hs
@@ -4,8 +4,9 @@
 
 module Test.Marionette.Client where
 
-import Control.Exception (AssertionFailed (AssertionFailed))
-import Control.Monad (void, when)
+import Control.Applicative ((<|>))
+import Control.Exception (AssertionFailed (AssertionFailed), SomeException)
+import Control.Monad (void, (<=<))
 import Control.Monad.Catch
     ( Exception (..)
     , MonadCatch
@@ -13,6 +14,7 @@
     , MonadThrow
     , catch
     , catchAll
+    , finally
     , throwM
     )
 import Control.Monad.Error.Class (MonadError (..))
@@ -27,9 +29,10 @@
 import Data.Binary qualified as Binary
 import Data.Binary.Get qualified as Binary
 import Data.ByteString (ByteString)
+import Data.ByteString qualified as BS
 import Data.ByteString.Builder.Extra qualified as ByteString
+import Data.IntMap (IntMap)
 import Data.IntMap.Strict qualified as IntMap
-import Data.Maybe (isNothing)
 import GHC.Stack (HasCallStack)
 import Network.Simple.TCP
     ( HostName
@@ -40,6 +43,7 @@
     , connectSock
     , sendLazy
     )
+import Network.Socket (PortNumber)
 import Network.Socket.ByteString (recv)
 import System.Timeout (timeout)
 import Test.Marionette.Class (Marionette (..))
@@ -54,10 +58,10 @@
     , link
     , readTMVar
     )
-import UnliftIO.Concurrent (forkIO)
 import UnliftIO.Retry (constantDelay, limitRetriesByCumulativeDelay, recoverAll)
 import UnliftIO.STM
-    ( atomically
+    ( TVar
+    , atomically
     , modifyTVar'
     , newEmptyTMVarIO
     , newTQueueIO
@@ -65,6 +69,7 @@
     , putTMVar
     , readTQueue
     , stateTVar
+    , tryPutTMVar
     , writeTQueue
     )
 import Prelude hiding (log)
@@ -79,12 +84,13 @@
 
 incoming
     :: forall m a
-     . (MonadUnliftIO m, MonadThrow m, Binary a)
+     . (MonadUnliftIO m, MonadCatch m, Binary a)
     => Socket
+    -> (SomeException -> m ())
     -> m (TQueue a)
-incoming socket = do
+incoming socket onFailure = do
     q <- newTQueueIO
-    link =<< async (go (atomically . writeTQueue q) (newDecoder ""))
+    void . async $ go (atomically . writeTQueue q) (newDecoder "") `catch` onFailure
     pure q
   where
     newDecoder :: ByteString -> Binary.Decoder a
@@ -93,10 +99,12 @@
     go f (Binary.Done rest _ a) = do
         f a
         go f $ newDecoder rest
-    go f dec =
-        go f . (dec `Binary.pushChunk`)
-            =<< liftIO
-                (recv socket ByteString.defaultChunkSize `catchAll` \_ -> throwM SocketClosed)
+    go f dec = do
+        chunk <-
+            liftIO (recv socket ByteString.defaultChunkSize `catchAll` \_ -> throwM SocketClosed)
+        if BS.null chunk
+            then throwM SocketClosed
+            else go f (dec `Binary.pushChunk` chunk)
 
 connect
     :: (MonadUnliftIO m)
@@ -112,19 +120,26 @@
         )
         (closeSock . fst)
 
-newtype MarionetteTimeout = MarionetteTimeout MarionetteMessage
+newtype MarionetteTimeout = MarionetteTimeout Command
     deriving stock (Show)
     deriving anyclass (Exception)
 
-newtype UnexpectedResult = UnexpectedResult Result
-    deriving stock (Show)
-    deriving anyclass (Exception)
+data QueuedCommand = QueuedCommand Int Command
 
-data CommandWithCallback = CommandWithCallback Command (TMVar Result)
+data ClientEnv = ClientEnv
+    { sendQueue :: TQueue QueuedCommand
+    , connectionLost :: TMVar SomeException
+    , commandTimeout :: Int
+    , nextMessageId :: TVar Int
+    , pendingCommands :: TVar (IntMap (TMVar Result))
+    }
 
--- | A monad transformer that speaks the Marionette wire protocol over a TCP
--- socket. Run it with 'runMarionetteT'.
-newtype MarionetteT m a = MarionetteT (ReaderT (TQueue CommandWithCallback) m a)
+defaultCommandTimeout :: Int
+defaultCommandTimeout = 15_000_000
+
+-- | A monad transformer that speaks the Marionette wire protocol over a TCP socket.
+-- Run it with 'runMarionetteT'.
+newtype MarionetteT m a = MarionetteT (ReaderT ClientEnv m a)
     deriving newtype
         ( Functor
         , Applicative
@@ -134,16 +149,29 @@
         , MonadMask
         , MonadIO
         , MonadUnliftIO
-        , MonadReader (TQueue CommandWithCallback)
+        , MonadReader ClientEnv
         )
 
 instance (MonadUnliftIO m, MonadThrow m, MonadCatch m) => Marionette (MarionetteT m) where
     sendCommand :: (HasCallStack, FromJSON a) => Command -> MarionetteT m a
     sendCommand command = do
-        q <- Reader.ask
+        ClientEnv{..} <- Reader.ask
         result <- newEmptyTMVarIO
-        atomically . writeTQueue q $ CommandWithCallback command result
-        either throwM pure =<< parseResult =<< atomically (readTMVar result)
+        messageId <- atomically do
+            messageId <- stateTVar nextMessageId $ \n -> (n, n + 1)
+            modifyTVar' pendingCommands $ IntMap.insert messageId result
+            writeTQueue sendQueue $ QueuedCommand messageId command
+            pure messageId
+        outcome <-
+            liftIO . timeout commandTimeout . atomically $
+                (Right <$> readTMVar result) <|> (Left <$> readTMVar connectionLost)
+        case outcome of
+            Nothing -> atomically . modifyTVar' pendingCommands $ IntMap.delete messageId
+            Just _ -> pure ()
+        maybe
+            (throwM . MarionetteTimeout $ command)
+            (either throwM (either throwM pure <=< parseResult))
+            outcome
       where
         parseResult :: (FromJSON a) => Result -> MarionetteT m (Either Error a)
         parseResult =
@@ -155,16 +183,20 @@
     throwError = throwM
     catchError = catch
 
--- | Connect to a Marionette server listening on @localhost:2828@ (started
--- by launching Firefox with the @--marionette@ flag), and run the given
--- action against it.
-runMarionetteT
+-- | Run an action against a Marionette server.
+runMarionetteTWith
     :: forall m a
      . (MonadUnliftIO m, MonadMask m)
-    => MarionetteT m a
+    => HostName
+    -> PortNumber
+    -> Int
+    -- ^ Command timeout, in microseconds.
+    -> MarionetteT m a
     -> m a
-runMarionetteT action = do
-    sendQueue :: TQueue CommandWithCallback <- newTQueueIO
+runMarionetteTWith host port commandTimeout action = do
+    sendQueue :: TQueue QueuedCommand <- newTQueueIO
+    connectionLost <- newEmptyTMVarIO
+    nextMessageId <- newTVarIO 1
     pendingCommands <- newTVarIO mempty
     done <- newEmptyTMVarIO
     let repeatUntilDone :: forall m'. (MonadIO m') => m' () -> m' ()
@@ -180,44 +212,45 @@
                         IntMap.updateLookupWithKey (\_ _ -> Nothing) messageId
                     )
                     >>= \case
-                        Nothing -> throwM . UnexpectedResult $ messageContent
+                        Nothing -> pure () -- a late or unsolicited reply; not fatal
                         Just result -> atomically $ putTMVar result messageContent
-        handleCommand :: Socket -> Int -> CommandWithCallback -> MarionetteT m ()
-        handleCommand socket messageId (CommandWithCallback messageContent callback) = do
-            let message = MarionetteMessage . Aeson.encode $ Message{..}
-            liftIO . sendLazy socket . Binary.encode $ message
-            forkIO do
-                result <- liftIO . timeout 5_000_000 . atomically . readTMVar $ callback
-                when (isNothing result) . throwM . MarionetteTimeout $ message
-            atomically . modifyTVar' pendingCommands $
-                IntMap.insert messageId callback
+        failPending :: SomeException -> MarionetteT m ()
+        failPending = void . atomically . tryPutTMVar connectionLost
+        handleCommand :: Socket -> QueuedCommand -> MarionetteT m ()
+        handleCommand socket (QueuedCommand messageId messageContent) =
+            liftIO . sendLazy socket . Binary.encode . MarionetteMessage . Aeson.encode $
+                Message{..}
         runSocket :: MarionetteT m ()
         runSocket =
-            connect "localhost" "2828" \(socket, _) -> do
-                incomingQueue <- incoming socket
+            connect host (show port) \(socket, _) -> do
+                incomingQueue <- incoming socket failPending
                 void . decodeMarionetteM @_ @Greeting =<< atomically (readTQueue incomingQueue)
-                let send messageId =
+                let send =
                         atomically
                             ( isEmptyTMVar done >>= \case
                                 True -> Just <$> readTQueue sendQueue
                                 False -> pure Nothing
                             )
-                            >>= \case
-                                Nothing -> pure ()
-                                Just command -> do
-                                    handleCommand socket messageId command
-                                    send $ messageId + 1
-                forkIO $ send 1
-                forkIO . repeatUntilDone $ handleIncoming =<< atomically (readTQueue incomingQueue)
+                            >>= maybe (pure ()) ((>> send) . handleCommand socket)
+                linkedAsync send
+                void . async $
+                    repeatUntilDone (handleIncoming =<< atomically (readTQueue incomingQueue))
+                        `catch` failPending
                 atomically $ readTMVar done
-    flip runReaderT sendQueue . (\(MarionetteT r) -> r) $ do
-        forkIO runSocket
-        a <- action
-        atomically $ putTMVar done ()
-        pure a
+    flip runReaderT ClientEnv{..} . (\(MarionetteT r) -> r) $ do
+        linkedAsync runSocket
+        action `finally` atomically (void $ tryPutTMVar done ())
   where
+    linkedAsync :: MarionetteT m () -> MarionetteT m ()
+    linkedAsync = link <=< async
+
     decodeMarionetteM :: forall m' a'. (MonadThrow m', FromJSON a') => MarionetteMessage -> m' a'
     decodeMarionetteM = either (throwM . AssertionFailed) pure . decodeMarionette
 
     decodeMarionette :: forall a'. (FromJSON a') => MarionetteMessage -> Either String a'
     decodeMarionette (MarionetteMessage lbs) = Aeson.eitherDecode lbs
+
+-- | Run an action against a Marionette server listening on @localhost:2828@
+-- (started by launching Firefox with the @--marionette@ flag).
+runMarionetteT :: (MonadUnliftIO m, MonadMask m) => MarionetteT m a -> m a
+runMarionetteT = runMarionetteTWith "localhost" 2828 defaultCommandTimeout
diff --git a/src/Test/Marionette/Commands.hs b/src/Test/Marionette/Commands.hs
--- a/src/Test/Marionette/Commands.hs
+++ b/src/Test/Marionette/Commands.hs
@@ -19,6 +19,7 @@
 import GHC.Generics (Generic)
 import GHC.Stack (HasCallStack)
 import Test.Marionette.AccessibilityProperties (AccessibilityProperties)
+import Test.Marionette.Actions (InputSource)
 import Test.Marionette.Class
 import Test.Marionette.Context (Context)
 import Test.Marionette.Cookie (Cookie)
@@ -53,8 +54,7 @@
 
 type role ValueObject representational
 
--- | Enable or disable accepting new socket connections.
--- This has no effect on existing connections.
+-- | Enable or disable accepting new socket connections. Has no effect on existing connections.
 acceptConnections :: (HasCallStack, Marionette m) => Bool -> m ()
 acceptConnections value =
     sendCommand_
@@ -63,8 +63,8 @@
             , parameters = Aeson.object ["value" .= value]
             }
 
--- | Look up accessibility properties of a node in the platform accessibility tree,
--- rather than by a web element reference.
+-- | Look up accessibility properties of a node in the platform accessibility tree, rather than
+-- by a web element reference.
 getAccessibilityPropertiesForAccessibilityNode
     :: (HasCallStack, Marionette m)
     => Text
@@ -77,8 +77,7 @@
             , parameters = Aeson.object ["nodeId" .= nodeId]
             }
 
--- | Look up the accessibility properties exposed to assistive technology
--- (such as screen readers) for a given element.
+-- | Look up the accessibility properties exposed to assistive technology for a given element.
 getAccessibilityPropertiesForElement
     :: (HasCallStack, Marionette m)
     => Element
@@ -90,11 +89,9 @@
             , parameters = Aeson.object ["id" .= elementId]
             }
 
--- | Return whether subsequent browsing-context-scoped commands (such as
--- 'navigate' or 'findElement') target privileged browser chrome or ordinary
--- web content.
--- New sessions start in the 'Content' context; use 'setContext' to switch,
--- for example when driving browser UI rather than a web page.
+-- | Return whether subsequent browsing-context-scoped commands target privileged browser chrome
+-- or ordinary web content.
+-- New sessions start in the 'Content' context.
 getContext :: (HasCallStack, Marionette m) => m Context
 getContext = value <$> sendCommand "Marionette:GetContext"
 
@@ -102,21 +99,20 @@
 getScreenOrientation :: (HasCallStack, Marionette m) => m Orientation
 getScreenOrientation = value <$> sendCommand "Marionette:GetScreenOrientation"
 
--- | Return the chrome window's @windowtype@ attribute, for example
--- @navigator:browser@ for a normal browser window.
+-- | Return the chrome window's @windowtype@ attribute, for example @navigator:browser@ for a
+-- normal browser window.
 getWindowType :: (HasCallStack, Marionette m) => m Text
 getWindowType = value <$> sendCommand "Marionette:GetWindowType"
 
--- | Shut the browser down: Marionette first stops accepting new
--- connections, then ends the current session, and finally causes the
--- application itself to quit.
+-- | Shut the browser down: Marionette first stops accepting new connections, then ends the
+-- current session, and finally causes the application itself to quit.
 quit :: (HasCallStack, Marionette m) => m ()
 quit = sendCommand_ "Marionette:Quit"
 
--- | Register a chrome protocol handler for a directory containing XHTML or
--- XUL files, allowing them to be loaded via the @chrome://@ protocol.
--- Return the identifier for the registered handler which can be unregistered
--- with 'unregisterChromeHandler'.
+-- | Register a chrome protocol handler for a directory containing XHTML or XUL files, allowing
+-- them to be loaded via the @chrome://@ protocol.
+-- Return the identifier for the registered handler which can be unregistered with
+-- 'unregisterChromeHandler'.
 registerChromeHandler :: (HasCallStack, Marionette m) => Text -> [RegistryEntry] -> m Text
 registerChromeHandler manifestPath entries =
     sendCommand
@@ -129,9 +125,8 @@
                     ]
             }
 
--- | Set the context of the subsequent commands. All subsequent requests to
--- commands that in some way involve interaction with a browsing context
--- will target the chosen context.
+-- | Set the context of the subsequent commands. All subsequent requests to commands that in some
+-- way involve interaction with a browsing context will target the chosen context.
 setContext :: (HasCallStack, Marionette m) => Context -> m ()
 setContext value =
     sendCommand_
@@ -149,8 +144,8 @@
             , parameters = Aeson.object ["orientation" .= orientation]
             }
 
--- | Unregister a previously registered chrome protocol handler, given an
--- identifier returned by 'registerChromeHandler'.
+-- | Unregister a previously registered chrome protocol handler, given an identifier returned by
+-- 'registerChromeHandler'.
 unregisterChromeHandler :: (HasCallStack, Marionette m) => Text -> m ()
 unregisterChromeHandler handlerId =
     sendCommand_
@@ -159,17 +154,15 @@
             , parameters = Aeson.object ["id" .= handlerId]
             }
 
--- | Accept a currently displayed dialog modal, or throw if no modal is
--- displayed.
+-- | Accept a currently displayed dialog modal, or throw if no modal is displayed.
 --
--- See <https://w3c.github.io/webdriver/#accept-alert>
+-- See <https://w3c.github.io/webdriver/#accept-alert>.
 acceptAlert :: (HasCallStack, Marionette m) => m ()
 acceptAlert = sendCommand_ "WebDriver:AcceptAlert"
 
--- | Add a single cookie to the cookie store associated with the active
--- document's address.
+-- | Add a single cookie to the cookie store associated with the active document's address.
 --
--- See <https://w3c.github.io/webdriver/#add-cookie>
+-- See <https://w3c.github.io/webdriver/#add-cookie>.
 addCookie :: (HasCallStack, Marionette m) => Cookie -> m ()
 addCookie cookie =
     sendCommand_
@@ -178,36 +171,33 @@
             , parameters = Aeson.object ["cookie" .= cookie]
             }
 
--- | Cause the browser to traverse one step backward in the joint history
--- of the current browsing context.
+-- | Traverse one step backward in the history of the current browsing context.
 --
--- See <https://w3c.github.io/webdriver/#back>
+-- See <https://w3c.github.io/webdriver/#back>.
 back :: (HasCallStack, Marionette m) => m ()
 back = sendCommand_ "WebDriver:Back"
 
--- | Close the currently selected chrome window. If it is the last window
--- currently open, the chrome window is not closed, to prevent an
--- application shutdown.
+-- | Close the currently selected chrome window.
+-- Does not close the last window currently open to prevent an application shutdown.
 closeChromeWindow :: (HasCallStack, Marionette m) => m ()
 closeChromeWindow = sendCommand_ "WebDriver:CloseChromeWindow"
 
--- | Close the currently selected tab or window. With multiple open tabs,
--- only the selected tab is closed; if it is the last window currently
--- open, the window is not closed, to prevent an application shutdown.
+-- | Close the currently selected tab or window.
+-- Does not close the last window currently open to prevent an application shutdown.
 --
--- See <https://w3c.github.io/webdriver/#close-window>
+-- See <https://w3c.github.io/webdriver/#close-window>.
 closeWindow :: (HasCallStack, Marionette m) => m ()
 closeWindow = sendCommand_ "WebDriver:CloseWindow"
 
 -- | Delete all cookies that are visible to a document.
 --
--- See <https://w3c.github.io/webdriver/#delete-all-cookies>
+-- See <https://w3c.github.io/webdriver/#delete-all-cookies>.
 deleteAllCookies :: (HasCallStack, Marionette m) => m ()
 deleteAllCookies = sendCommand_ "WebDriver:DeleteAllCookies"
 
 -- | Delete a cookie by name.
 --
--- See <https://w3c.github.io/webdriver/#delete-cookie>
+-- See <https://w3c.github.io/webdriver/#delete-cookie>.
 deleteCookie :: (HasCallStack, Marionette m) => Text -> m ()
 deleteCookie name =
     sendCommand_
@@ -218,20 +208,20 @@
 
 -- | Delete the current WebDriver session.
 --
--- See <https://w3c.github.io/webdriver/#delete-session>
+-- See <https://w3c.github.io/webdriver/#delete-session>.
 deleteSession :: (HasCallStack, Marionette m) => m ()
 deleteSession = sendCommand_ "WebDriver:DeleteSession"
 
 -- | Dismiss a currently displayed modal dialog, or throw if no modal is
 -- displayed.
 --
--- See <https://w3c.github.io/webdriver/#dismiss-alert>
+-- See <https://w3c.github.io/webdriver/#dismiss-alert>.
 dismissAlert :: (HasCallStack, Marionette m) => m ()
 dismissAlert = sendCommand_ "WebDriver:DismissAlert"
 
 -- | Clear the text of an element.
 --
--- See <https://w3c.github.io/webdriver/#element-clear>
+-- See <https://w3c.github.io/webdriver/#element-clear>.
 elementClear :: (HasCallStack, Marionette m) => Element -> m ()
 elementClear Element{..} =
     sendCommand_
@@ -242,7 +232,7 @@
 
 -- | Send a click event to an element.
 --
--- See <https://w3c.github.io/webdriver/#element-click>
+-- See <https://w3c.github.io/webdriver/#element-click>.
 elementClick :: (HasCallStack, Marionette m) => Element -> m ()
 elementClick Element{..} =
     sendCommand_
@@ -253,7 +243,7 @@
 
 -- | Send key presses to an element after focusing on it.
 --
--- See <https://w3c.github.io/webdriver/#element-send-keys>
+-- See <https://w3c.github.io/webdriver/#element-send-keys>.
 elementSendKeys :: (HasCallStack, Marionette m) => Element -> Text -> m ()
 elementSendKeys Element{..} text =
     sendCommand_
@@ -266,11 +256,10 @@
                     ]
             }
 
--- | Execute a JavaScript function asynchronously in the context of the
--- current browsing context, and return the value passed to the callback,
--- which is always the last argument exposed to the script.
+-- | Execute a JavaScript function asynchronously in the context of the current browsing context,
+-- and return the value passed to the callback, which is the last argument exposed to the script.
 --
--- See <https://w3c.github.io/webdriver/#execute-async-script>
+-- See <https://w3c.github.io/webdriver/#execute-async-script>.
 executeAsyncScript
     :: (HasCallStack, Marionette m, Foldable f, FromJSON a)
     => Text
@@ -287,10 +276,10 @@
                     ]
             }
 
--- | Execute a JavaScript function synchronously in the context of the
--- current browsing context, and return its return value.
+-- | Execute a JavaScript function synchronously in the context of the current browsing context,
+-- and return its return value.
 --
--- See <https://w3c.github.io/webdriver/#execute-script>
+-- See <https://w3c.github.io/webdriver/#execute-script>.
 executeScript :: (HasCallStack, Marionette m, Foldable f, FromJSON a) => Text -> f Value -> m a
 executeScript script args =
     fmap value . sendCommand $
@@ -305,7 +294,7 @@
 
 -- | Find an element using the given search strategy.
 --
--- See <https://w3c.github.io/webdriver/#find-element>
+-- See <https://w3c.github.io/webdriver/#find-element>.
 findElement :: (HasCallStack, Marionette m) => Selector -> m Element
 findElement selector =
     value
@@ -315,10 +304,9 @@
                 , parameters = toJSON selector
                 }
 
--- | Find an element using the given search strategy, relative to the
--- given element.
+-- | Find an element using the given search strategy, relative to the given element.
 --
--- See <https://w3c.github.io/webdriver/#find-element>
+-- See <https://w3c.github.io/webdriver/#find-element>.
 findElementFrom :: (HasCallStack, Marionette m) => Element -> Selector -> m Element
 findElementFrom element selector =
     value
@@ -330,7 +318,7 @@
 
 -- | Find an element within a shadow root using the given search strategy.
 --
--- See <https://w3c.github.io/webdriver/#find-element-from-shadow-root>
+-- See <https://w3c.github.io/webdriver/#find-element-from-shadow-root>.
 findElementFromShadowRoot :: (HasCallStack, Marionette m) => Shadow -> Selector -> m Element
 findElementFromShadowRoot shadowRoot selector =
     value
@@ -342,7 +330,7 @@
 
 -- | Find elements using the given search strategy.
 --
--- See <https://w3c.github.io/webdriver/#find-elements>
+-- See <https://w3c.github.io/webdriver/#find-elements>.
 findElements :: (HasCallStack, Marionette m) => Selector -> m [Element]
 findElements selector =
     sendCommand
@@ -351,10 +339,9 @@
             , parameters = toJSON selector
             }
 
--- | Find elements using the given search strategy, relative to the given
--- element.
+-- | Find elements using the given search strategy, relative to the given element.
 --
--- See <https://w3c.github.io/webdriver/#find-elements>
+-- See <https://w3c.github.io/webdriver/#find-elements>.
 findElementsFrom :: (HasCallStack, Marionette m) => Element -> Selector -> m [Element]
 findElementsFrom element selector =
     sendCommand
@@ -365,7 +352,7 @@
 
 -- | Find elements within a shadow root using the given search strategy.
 --
--- See <https://w3c.github.io/webdriver/#find-elements-from-shadow-root>
+-- See <https://w3c.github.io/webdriver/#find-elements-from-shadow-root>.
 findElementsFromShadowRoot :: (HasCallStack, Marionette m) => Shadow -> Selector -> m [Element]
 findElementsFromShadowRoot shadowRoot selector =
     sendCommand
@@ -374,36 +361,33 @@
             , parameters = toJSON $ SelectorFromShadowRoot shadowRoot selector
             }
 
--- | Cause the browser to traverse one step forward in the joint history
--- of the current browsing context.
+-- | Traverse one step forward in the history of the current browsing context.
 --
--- See <https://w3c.github.io/webdriver/#forward>
+-- See <https://w3c.github.io/webdriver/#forward>.
 forward :: (HasCallStack, Marionette m) => m ()
 forward = sendCommand_ "WebDriver:Forward"
 
--- | Set the window to full screen, as if the user had chosen
--- View -> Enter Full Screen. Not supported on Android.
+-- | Set the window to full screen. Not supported on Android.
 --
--- See <https://w3c.github.io/webdriver/#fullscreen-window>
+-- See <https://w3c.github.io/webdriver/#fullscreen-window>.
 fullscreenWindow :: (HasCallStack, Marionette m) => m ()
 fullscreenWindow = sendCommand_ "WebDriver:FullscreenWindow"
 
 -- | Return the active element in the document.
 --
--- See <https://w3c.github.io/webdriver/#get-active-element>
+-- See <https://w3c.github.io/webdriver/#get-active-element>.
 getActiveElement :: (HasCallStack, Marionette m) => m Element
 getActiveElement = value <$> sendCommand "WebDriver:GetActiveElement"
 
--- | Return the message shown in a currently displayed modal, or throw if
--- no modal is displayed.
+-- | Return the message shown in a currently displayed modal, or throw if no modal is displayed.
 --
--- See <https://w3c.github.io/webdriver/#get-alert-text>
+-- See <https://w3c.github.io/webdriver/#get-alert-text>.
 getAlertText :: (HasCallStack, Marionette m) => m Text
 getAlertText = value <$> sendCommand "WebDriver:GetAlertText"
 
 -- | Determine the accessibility label for an element.
 --
--- See <https://w3c.github.io/webdriver/#get-computed-label>
+-- See <https://w3c.github.io/webdriver/#get-computed-label>.
 getComputedLabel :: (HasCallStack, Marionette m) => Element -> m Text
 getComputedLabel Element{..} =
     value
@@ -415,7 +399,7 @@
 
 -- | Determine the accessibility role for an element.
 --
--- See <https://w3c.github.io/webdriver/#get-computed-role>
+-- See <https://w3c.github.io/webdriver/#get-computed-role>.
 getComputedRole :: (HasCallStack, Marionette m) => Element -> m Text
 getComputedRole Element{..} =
     value
@@ -425,24 +409,23 @@
                 , parameters = Aeson.object ["id" .= elementId]
                 }
 
--- | Get all the cookies for the current domain. Equivalent to calling
--- @document.cookie@ and parsing the result.
+-- | Get all the cookies for the current domain. Equivalent to calling @document.cookie@ and
+-- parsing the result.
 --
--- See <https://w3c.github.io/webdriver/#get-all-cookies>
+-- See <https://w3c.github.io/webdriver/#get-all-cookies>.
 getCookies :: (HasCallStack, Marionette m) => m [Cookie]
 getCookies = sendCommand "WebDriver:GetCookies"
 
--- | Get a string representing the current URL, equivalent to
--- @document.location.href@. When in the chrome context, return the
--- canonical URL of the current resource.
+-- | Get a string representing the current URL, equivalent to @document.location.href@.
+-- When in the chrome context, return the canonical URL of the current resource.
 --
--- See <https://w3c.github.io/webdriver/#get-current-url>
+-- See <https://w3c.github.io/webdriver/#get-current-url>.
 getCurrentURL :: (HasCallStack, Marionette m) => m Text
 getCurrentURL = value <$> sendCommand "WebDriver:GetCurrentURL"
 
 -- | Get the value of the given attribute of an element.
 --
--- See <https://w3c.github.io/webdriver/#get-element-attribute>
+-- See <https://w3c.github.io/webdriver/#get-element-attribute>.
 getElementAttribute :: (HasCallStack, Marionette m) => Text -> Element -> m (Maybe Text)
 getElementAttribute attr Element{..} =
     value
@@ -458,7 +441,7 @@
 
 -- | Get the given CSS property of the computed style of an element.
 --
--- See <https://w3c.github.io/webdriver/#get-element-css-value>
+-- See <https://w3c.github.io/webdriver/#get-element-css-value>.
 getElementCSSValue :: (HasCallStack, Marionette m) => Element -> Text -> m (Maybe Text)
 getElementCSSValue Element{..} propertyName =
     value
@@ -474,7 +457,7 @@
 
 -- | Get the value of the given property of an element.
 --
--- See <https://w3c.github.io/webdriver/#get-element-property>
+-- See <https://w3c.github.io/webdriver/#get-element-property>.
 getElementProperty :: (HasCallStack, Marionette m) => Element -> Text -> m (Maybe Text)
 getElementProperty Element{..} name =
     value
@@ -490,7 +473,7 @@
 
 -- | Get the dimensions and coordinates of an element.
 --
--- See <https://w3c.github.io/webdriver/#get-element-rect>
+-- See <https://w3c.github.io/webdriver/#get-element-rect>.
 getElementRect :: (HasCallStack, Marionette m) => Element -> m Rect
 getElementRect Element{..} =
     sendCommand
@@ -501,7 +484,7 @@
 
 -- | Get the local tag name of an element.
 --
--- See <https://w3c.github.io/webdriver/#get-element-tag-name>
+-- See <https://w3c.github.io/webdriver/#get-element-tag-name>.
 getElementTagName :: (HasCallStack, Marionette m) => Element -> m Text
 getElementTagName Element{..} =
     value
@@ -511,10 +494,9 @@
                 , parameters = Aeson.object ["id" .= elementId]
                 }
 
--- | Get the rendered text of an element, including the text of all its
--- child elements.
+-- | Get the rendered text of an element, including the text of all its child elements.
 --
--- See <https://w3c.github.io/webdriver/#get-element-text>
+-- See <https://w3c.github.io/webdriver/#get-element-text>.
 getElementText :: (HasCallStack, Marionette m) => Element -> m Text
 getElementText Element{..} =
     value
@@ -526,13 +508,13 @@
 
 -- | Get the page source of the content document, serialised as a string.
 --
--- See <https://w3c.github.io/webdriver/#get-page-source>
+-- See <https://w3c.github.io/webdriver/#get-page-source>.
 getPageSource :: (HasCallStack, Marionette m) => m Text
 getPageSource = value <$> sendCommand "WebDriver:GetPageSource"
 
 -- | Get the shadow root of an element.
 --
--- See <https://w3c.github.io/webdriver/#get-element-shadow-root>
+-- See <https://w3c.github.io/webdriver/#get-element-shadow-root>.
 getShadowRoot :: (HasCallStack, Marionette m) => Element -> m Shadow
 getShadowRoot Element{..} =
     value
@@ -544,42 +526,40 @@
 
 -- | Get the timeouts for page loading, searching, and scripts.
 --
--- See <https://w3c.github.io/webdriver/#get-timeouts>
+-- See <https://w3c.github.io/webdriver/#get-timeouts>.
 getTimeouts :: (HasCallStack, Marionette m) => m Timeouts
 getTimeouts = sendCommand "WebDriver:GetTimeouts"
 
 -- | Get the current title of the window.
 --
--- See <https://w3c.github.io/webdriver/#get-title>
+-- See <https://w3c.github.io/webdriver/#get-title>.
 getTitle :: (HasCallStack, Marionette m) => m Text
 getTitle = value <$> sendCommand "WebDriver:GetTitle"
 
--- | Get the current window's handle: an opaque, server-assigned
--- identifier that can be used to switch back to this window later with
--- 'switchToWindow'.
+-- | Get the current window's handle: an opaque, server-assigned identifier
+-- that can be used to switch back to this window later with 'switchToWindow'.
 --
--- See <https://w3c.github.io/webdriver/#get-window-handle>
+-- See <https://w3c.github.io/webdriver/#get-window-handle>.
 getWindowHandle :: (HasCallStack, Marionette m) => m WindowHandle
 getWindowHandle = value <$> sendCommand "WebDriver:GetWindowHandle"
 
--- | Get the unordered list of window handles of every open top-level
--- browsing context.
+-- | Get the unordered list of window handles of every open top-level browsing context.
 --
--- See <https://w3c.github.io/webdriver/#get-window-handles>
+-- See <https://w3c.github.io/webdriver/#get-window-handles>.
 getWindowHandles :: (HasCallStack, Marionette m) => m [WindowHandle]
 getWindowHandles = sendCommand "WebDriver:GetWindowHandles"
 
 -- | Get the position and size of the browser window currently in focus.
--- The width and height refer to the window's @outerWidth@ and
--- @outerHeight@, which include scroll bars, title bars, and so on.
+-- The width and height refer to the window's @outerWidth@ and @outerHeight@,
+-- which include scroll bars, title bars, and so on.
 --
--- See <https://w3c.github.io/webdriver/#get-window-rect>
+-- See <https://w3c.github.io/webdriver/#get-window-rect>.
 getWindowRect :: (HasCallStack, Marionette m) => m Rect
 getWindowRect = sendCommand "WebDriver:GetWindowRect"
 
 -- | Check whether an element is displayed.
 --
--- See <https://w3c.github.io/webdriver/#element-displayedness>
+-- See <https://w3c.github.io/webdriver/#element-displayedness>.
 isElementDisplayed :: (HasCallStack, Marionette m) => Element -> m Bool
 isElementDisplayed Element{..} =
     value
@@ -591,7 +571,7 @@
 
 -- | Check whether an element is enabled.
 --
--- See <https://w3c.github.io/webdriver/#is-element-enabled>
+-- See <https://w3c.github.io/webdriver/#is-element-enabled>.
 isElementEnabled :: (HasCallStack, Marionette m) => Element -> m Bool
 isElementEnabled Element{..} =
     value
@@ -603,7 +583,7 @@
 
 -- | Check whether an element is selected.
 --
--- See <https://w3c.github.io/webdriver/#is-element-selected>
+-- See <https://w3c.github.io/webdriver/#is-element-selected>.
 isElementSelected :: (HasCallStack, Marionette m) => Element -> m Bool
 isElementSelected Element{..} =
     value
@@ -616,21 +596,21 @@
 -- | Maximise the window, as if the user had pressed the maximise button.
 -- Not supported on Android.
 --
--- See <https://w3c.github.io/webdriver/#maximize-window>
+-- See <https://w3c.github.io/webdriver/#maximize-window>.
 maximizeWindow :: (HasCallStack, Marionette m) => m ()
 maximizeWindow = sendCommand_ "WebDriver:MaximizeWindow"
 
 -- | Minimise the window, as if the user had pressed the minimise button.
 -- Not supported on Android.
 --
--- See <https://w3c.github.io/webdriver/#minimize-window>
+-- See <https://w3c.github.io/webdriver/#minimize-window>.
 minimizeWindow :: (HasCallStack, Marionette m) => m ()
 minimizeWindow = sendCommand_ "WebDriver:MinimizeWindow"
 
--- | Navigate to the given URL, waiting for the document to load or the
--- session's page load timeout to elapse before returning.
+-- | Navigate to the given URL, waiting for the document to load or the session's page load
+-- timeout to elapse before returning.
 --
--- See <https://w3c.github.io/webdriver/#navigate-to>
+-- See <https://w3c.github.io/webdriver/#navigate-to>.
 navigate :: (HasCallStack, Marionette m) => Text -> m ()
 navigate url =
     sendCommand_
@@ -639,16 +619,15 @@
             , parameters = Aeson.object ["url" .= url]
             }
 
--- | Create a new WebDriver session. Must be called before performing any
--- other command.
+-- | Create a new WebDriver session. Must be called before performing any other command.
 --
--- See <https://w3c.github.io/webdriver/#new-session>
+-- See <https://w3c.github.io/webdriver/#new-session>.
 newSession :: (HasCallStack, Marionette m) => m ()
 newSession = sendCommand_ "WebDriver:NewSession"
 
 -- | Open a new top-level browsing context of type window.
 --
--- See <https://w3c.github.io/webdriver/#new-window>
+-- See <https://w3c.github.io/webdriver/#new-window>.
 newWindow :: (HasCallStack, Marionette m) => m NewWindowResult
 newWindow =
     sendCommand
@@ -659,7 +638,7 @@
 
 -- | Open a new top-level browsing context of type tab.
 --
--- See <https://w3c.github.io/webdriver/#new-window>
+-- See <https://w3c.github.io/webdriver/#new-window>.
 newTab :: (HasCallStack, Marionette m) => m NewWindowResult
 newTab =
     sendCommand
@@ -668,37 +647,39 @@
             , parameters = Aeson.object ["type" .= Tab]
             }
 
--- | Perform a series of grouped input actions at the specified points in
--- time.
+-- | Perform a series of grouped input actions at the specified points in time.
 --
--- See <https://w3c.github.io/webdriver/#perform-actions>
-performActions :: (HasCallStack, Marionette m) => m ()
-performActions = sendCommand_ "WebDriver:PerformActions"
+-- See <https://w3c.github.io/webdriver/#perform-actions>.
+performActions :: (HasCallStack, Marionette m) => [InputSource] -> m ()
+performActions actions =
+    sendCommand_
+        Command
+            { command = "WebDriver:PerformActions"
+            , parameters = Aeson.object ["actions" .= actions]
+            }
 
 -- | Print the current page, returning it as a base64-encoded PDF.
 --
--- See <https://w3c.github.io/webdriver/#print-page>
+-- See <https://w3c.github.io/webdriver/#print-page>.
 print :: (HasCallStack, Marionette m) => m ()
 print = sendCommand_ "WebDriver:Print"
 
 -- | Reload the page in the current top-level browsing context.
 --
--- See <https://w3c.github.io/webdriver/#refresh>
+-- See <https://w3c.github.io/webdriver/#refresh>.
 refresh :: (HasCallStack, Marionette m) => m ()
 refresh = sendCommand_ "WebDriver:Refresh"
 
--- | Release all the keys and pointer buttons that are currently
--- depressed.
+-- | Release all the keys and pointer buttons that are currently depressed.
 --
--- See <https://w3c.github.io/webdriver/#release-actions>
+-- See <https://w3c.github.io/webdriver/#release-actions>.
 releaseActions :: (HasCallStack, Marionette m) => m ()
 releaseActions = sendCommand_ "WebDriver:ReleaseActions"
 
--- | Send keys to the input field of a currently displayed modal, or
--- throw if no modal is displayed, or the modal has no means for text
--- input.
+-- | Send keys to the input field of a currently displayed modal, or throw if no modal is
+-- displayed, or the modal has no means for text input.
 --
--- See <https://w3c.github.io/webdriver/#send-alert-text>
+-- See <https://w3c.github.io/webdriver/#send-alert-text>.
 sendAlertText :: (HasCallStack, Marionette m) => Text -> m ()
 sendAlertText text =
     sendCommand_
@@ -707,16 +688,15 @@
             , parameters = Aeson.object ["text" .= text]
             }
 
--- | Simulate user modification of a permission descriptor's permission
--- state.
+-- | Simulate user modification of a permission descriptor's permission state.
 --
--- See <https://www.w3.org/TR/permissions/#webdriver-command-set-permission>
+-- See <https://www.w3.org/TR/permissions/#webdriver-command-set-permission>.
 setPermission :: (HasCallStack, Marionette m) => m ()
 setPermission = sendCommand_ "WebDriver:SetPermission"
 
 -- | Set the timeouts for page loading, searching, and scripts.
 --
--- See <https://w3c.github.io/webdriver/#set-timeouts>
+-- See <https://w3c.github.io/webdriver/#set-timeouts>.
 setTimeouts :: (HasCallStack, Marionette m) => Timeouts -> m ()
 setTimeouts timeouts =
     sendCommand_
@@ -725,12 +705,11 @@
             , parameters = toJSON timeouts
             }
 
--- | Set the position and size of the window on the operating system's
--- window manager. The width and height refer to the window's
--- @outerWidth@ and @outerHeight@, which include browser chrome and
--- OS-level window borders.
+-- | Set the position and size of the window on the operating system's window manager.
+-- The width and height refer to the window's @outerWidth@ and @outerHeight@, which include
+-- browser chrome and OS-level window borders.
 --
--- See <https://w3c.github.io/webdriver/#set-window-rect>
+-- See <https://w3c.github.io/webdriver/#set-window-rect>.
 setWindowRect :: (HasCallStack, Marionette m) => Rect -> m ()
 setWindowRect rect =
     sendCommand_
@@ -741,7 +720,7 @@
 
 -- | Switch to the given frame within the current window.
 --
--- See <https://w3c.github.io/webdriver/#switch-to-frame>
+-- See <https://w3c.github.io/webdriver/#switch-to-frame>.
 switchToFrame :: (HasCallStack, Marionette m) => Frame -> m ()
 switchToFrame frame =
     sendCommand_
@@ -750,17 +729,17 @@
             , parameters = toJSON frame
             }
 
--- | Set the current browsing context for future commands to the parent
--- of the current browsing context.
+-- | Set the current browsing context for future commands to the parent of the current browsing
+-- context.
 --
--- See <https://w3c.github.io/webdriver/#switch-to-parent-frame>
+-- See <https://w3c.github.io/webdriver/#switch-to-parent-frame>.
 switchToParentFrame :: (HasCallStack, Marionette m) => m ()
 switchToParentFrame = sendCommand_ "WebDriver:SwitchToParentFrame"
 
 -- | Switch to the top-level browsing context identified by the given
 -- window handle.
 --
--- See <https://w3c.github.io/webdriver/#switch-to-window>
+-- See <https://w3c.github.io/webdriver/#switch-to-window>.
 switchToWindow :: (HasCallStack, Marionette m) => WindowHandle -> m ()
 switchToWindow window =
     sendCommand_
@@ -769,10 +748,9 @@
             , parameters = toJSON window
             }
 
--- | Take a screenshot of the current frame, returned as a lossless PNG
--- image.
+-- | Take a screenshot of the current frame as a lossless PNG image.
 --
--- See <https://w3c.github.io/webdriver/#take-screenshot>
+-- See <https://w3c.github.io/webdriver/#take-screenshot>.
 takeScreenshot :: (HasCallStack, Marionette m) => m ByteString
 takeScreenshot =
     Base64.decodeLenient
@@ -786,7 +764,7 @@
 
 -- | Add a credential to a virtual authenticator.
 --
--- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-add-credential>
+-- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-add-credential>.
 addCredential :: (HasCallStack, Marionette m) => AuthenticatorId -> Credential -> m ()
 addCredential authenticatorId credential =
     sendCommand_
@@ -803,7 +781,7 @@
 
 -- | Add a virtual authenticator, returning its identifier.
 --
--- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-add-virtual-authenticator>
+-- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-add-virtual-authenticator>.
 addVirtualAuthenticator :: (HasCallStack, Marionette m) => VirtualAuthenticator -> m AuthenticatorId
 addVirtualAuthenticator authenticator =
     value
@@ -815,7 +793,7 @@
 
 -- | Get the credentials stored in a virtual authenticator.
 --
--- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-get-credentials>
+-- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-get-credentials>.
 getCredentials :: (HasCallStack, Marionette m) => AuthenticatorId -> m [Credential]
 getCredentials authenticatorId =
     value
@@ -827,7 +805,7 @@
 
 -- | Remove all credentials from a virtual authenticator.
 --
--- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-remove-all-credentials>
+-- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-remove-all-credentials>.
 removeAllCredentials :: (HasCallStack, Marionette m) => AuthenticatorId -> m ()
 removeAllCredentials authenticatorId =
     sendCommand_
@@ -838,7 +816,7 @@
 
 -- | Remove a credential from a virtual authenticator.
 --
--- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-remove-credential>
+-- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-remove-credential>.
 removeCredential :: (HasCallStack, Marionette m) => AuthenticatorId -> CredentialId -> m ()
 removeCredential authenticatorId credentialId =
     sendCommand_
@@ -853,7 +831,7 @@
 
 -- | Remove a virtual authenticator.
 --
--- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-remove-virtual-authenticator>
+-- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-remove-virtual-authenticator>.
 removeVirtualAuthenticator :: (HasCallStack, Marionette m) => AuthenticatorId -> m ()
 removeVirtualAuthenticator authenticatorId =
     sendCommand_
@@ -864,7 +842,7 @@
 
 -- | Set the user-verified flag on a virtual authenticator.
 --
--- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-set-user-verified>
+-- See <https://www.w3.org/TR/webauthn-3/#sctn-automation-set-user-verified>.
 setUserVerified :: (HasCallStack, Marionette m) => AuthenticatorId -> Bool -> m ()
 setUserVerified authenticatorId verified =
     sendCommand_
diff --git a/src/Test/Marionette/Key.hs b/src/Test/Marionette/Key.hs
new file mode 100644
--- /dev/null
+++ b/src/Test/Marionette/Key.hs
@@ -0,0 +1,129 @@
+module Test.Marionette.Key where
+
+import Data.Aeson (ToJSON (..), Value (String))
+import Data.Text qualified as Text
+import Prelude hiding (Left, Right)
+
+-- | Key values representing special keys and arbitrary characters, as defined in the
+-- <https://www.w3.org/TR/webdriver/#keyboard-actions W3C WebDriver specification>.
+data Key
+    = Null
+    | Cancel
+    | Help
+    | Backspace
+    | Tab
+    | Clear
+    | Return
+    | Enter
+    | Shift
+    | Control
+    | Alt
+    | Pause
+    | Escape
+    | Space
+    | PageUp
+    | PageDown
+    | End
+    | Home
+    | Left
+    | UpArrow
+    | Right
+    | DownArrow
+    | Insert
+    | Delete
+    | Semicolon
+    | Equals
+    | Numpad0
+    | Numpad1
+    | Numpad2
+    | Numpad3
+    | Numpad4
+    | Numpad5
+    | Numpad6
+    | Numpad7
+    | Numpad8
+    | Numpad9
+    | Multiply
+    | Add
+    | Separator
+    | Subtract
+    | Decimal
+    | Divide
+    | F1
+    | F2
+    | F3
+    | F4
+    | F5
+    | F6
+    | F7
+    | F8
+    | F9
+    | F10
+    | F11
+    | F12
+    | Meta
+    | ZenkakuHankaku
+    | Key Char
+    deriving stock (Show, Eq)
+
+char :: Key -> Char
+char Null = '\xE000'
+char Cancel = '\xE001'
+char Help = '\xE002'
+char Backspace = '\xE003'
+char Tab = '\xE004'
+char Clear = '\xE005'
+char Return = '\xE006'
+char Enter = '\xE007'
+char Shift = '\xE008'
+char Control = '\xE009'
+char Alt = '\xE00A'
+char Pause = '\xE00B'
+char Escape = '\xE00C'
+char Space = '\xE00D'
+char PageUp = '\xE00E'
+char PageDown = '\xE00F'
+char End = '\xE010'
+char Home = '\xE011'
+char Left = '\xE012'
+char UpArrow = '\xE013'
+char Right = '\xE014'
+char DownArrow = '\xE015'
+char Insert = '\xE016'
+char Delete = '\xE017'
+char Semicolon = '\xE018'
+char Equals = '\xE019'
+char Numpad0 = '\xE01A'
+char Numpad1 = '\xE01B'
+char Numpad2 = '\xE01C'
+char Numpad3 = '\xE01D'
+char Numpad4 = '\xE01E'
+char Numpad5 = '\xE01F'
+char Numpad6 = '\xE020'
+char Numpad7 = '\xE021'
+char Numpad8 = '\xE022'
+char Numpad9 = '\xE023'
+char Multiply = '\xE024'
+char Add = '\xE025'
+char Separator = '\xE026'
+char Subtract = '\xE027'
+char Decimal = '\xE028'
+char Divide = '\xE029'
+char F1 = '\xE031'
+char F2 = '\xE032'
+char F3 = '\xE033'
+char F4 = '\xE034'
+char F5 = '\xE035'
+char F6 = '\xE036'
+char F7 = '\xE037'
+char F8 = '\xE038'
+char F9 = '\xE039'
+char F10 = '\xE03A'
+char F11 = '\xE03B'
+char F12 = '\xE03C'
+char Meta = '\xE03D'
+char ZenkakuHankaku = '\xE040'
+char (Key c) = c
+
+instance ToJSON Key where
+    toJSON = String . Text.singleton . char
diff --git a/src/Test/Marionette/Protocol.hs b/src/Test/Marionette/Protocol.hs
--- a/src/Test/Marionette/Protocol.hs
+++ b/src/Test/Marionette/Protocol.hs
@@ -104,8 +104,7 @@
                         else Left <$> parseJSON err
             _ -> mzero
 
--- | An error reported by a Marionette or WebDriver command, as returned by
--- the server.
+-- | An error reported by a Marionette or WebDriver command, as returned by the server.
 --
 -- See <https://w3c.github.io/webdriver/#errors>
 data Error = Error
@@ -127,4 +126,4 @@
     , marionetteProtocol :: Int
     }
     deriving stock (Generic, Show)
-    deriving anyclass (FromJSON)
+    deriving anyclass (FromJSON, ToJSON)
diff --git a/src/Test/Marionette/Registry.hs b/src/Test/Marionette/Registry.hs
--- a/src/Test/Marionette/Registry.hs
+++ b/src/Test/Marionette/Registry.hs
@@ -6,8 +6,6 @@
 import GHC.Generics (Generic)
 import Prelude
 
--------------------------------------------------------------------
-
 data RegistryEntry = RegistryEntry
     { entryType :: Text
     , namespace :: Text
diff --git a/src/Test/Marionette/Selector.hs b/src/Test/Marionette/Selector.hs
--- a/src/Test/Marionette/Selector.hs
+++ b/src/Test/Marionette/Selector.hs
@@ -21,7 +21,7 @@
     | ByXPath Text
     | Anon Text
     | AnonAttribute Text
-    deriving stock (Generic, Eq, Show)
+    deriving stock (Generic, Eq, Ord, Show)
     deriving anyclass (Hashable)
 
 toObject :: Selector -> Object
diff --git a/test/ClientSpec.hs b/test/ClientSpec.hs
new file mode 100644
--- /dev/null
+++ b/test/ClientSpec.hs
@@ -0,0 +1,150 @@
+module Main where
+
+import Data.Aeson qualified as Aeson
+import Data.Binary qualified as Binary
+import Network.Simple.TCP
+    ( HostPreference (Host)
+    , Socket
+    , accept
+    , closeSock
+    , listen
+    , sendLazy
+    )
+import Network.Socket (PortNumber, socketPort)
+import Test.Hspec (describe, hspec, it)
+import Test.Hspec.Expectations.Lifted (shouldReturn, shouldSatisfy)
+import Test.Marionette.Class (sendCommand)
+import Test.Marionette.Client
+    ( MarionetteTimeout (..)
+    , SocketClosed (..)
+    , incoming
+    , runMarionetteTWith
+    )
+import Test.Marionette.Protocol
+import UnliftIO (TQueue, async, cancel, finally, timeout, try)
+import UnliftIO.STM (atomically, readTQueue)
+import Prelude
+
+withServer :: (Socket -> TQueue MarionetteMessage -> IO ()) -> (PortNumber -> IO a) -> IO a
+withServer serve body =
+    listen (Host "127.0.0.1") "0" \(listening, _) -> do
+        port <- socketPort listening
+        handling <-
+            async $ accept listening \(socket, _) ->
+                serve socket =<< incoming socket \_ -> pure ()
+        body port `finally` cancel handling
+
+send :: (Aeson.ToJSON a) => Socket -> a -> IO ()
+send socket = sendLazy socket . Binary.encode . MarionetteMessage . Aeson.encode
+
+recv :: TQueue MarionetteMessage -> IO (Message Command)
+recv frames = do
+    MarionetteMessage lbs <- atomically $ readTQueue frames
+    either fail pure $ Aeson.eitherDecode lbs
+
+greeting :: Greeting
+greeting = Greeting{applicationType = "fake", marionetteProtocol = 3}
+
+reply :: Socket -> Message Command -> Result -> IO ()
+reply socket Message{messageId} result =
+    send socket Message{messageId, messageContent = result}
+
+testCommandTimeout :: Int
+testCommandTimeout = 200_000
+
+main :: IO ()
+main = hspec do
+    describe "incoming" do
+        it "reports SocketClosed when the server hangs up" $
+            withServer
+                ( \socket _frames -> do
+                    send socket greeting
+                    closeSock socket
+                )
+                \port -> do
+                    outcome <-
+                        timeout 2_000_000 . try $
+                            runMarionetteTWith
+                                "127.0.0.1"
+                                port
+                                testCommandTimeout
+                                (sendCommand @_ @Aeson.Value "noop")
+
+                    outcome `shouldSatisfy` \case
+                        Just (Left SocketClosed) -> True
+                        _ -> False
+
+    describe "sendCommand" do
+        it "throws MarionetteTimeout without killing the session" $
+            withServer
+                ( \socket frames -> do
+                    send socket greeting
+                    _silent <- recv frames
+                    echoed <- recv frames
+                    reply socket echoed $ Right (Aeson.String "ok")
+                )
+                \port ->
+                    runMarionetteTWith "127.0.0.1" port testCommandTimeout do
+                        silent <- try $ sendCommand @_ @Aeson.Value "silent"
+                        silent `shouldSatisfy` \case
+                            Left MarionetteTimeout{} -> True
+                            _ -> False
+                        sendCommand "echo" `shouldReturn` Aeson.String "ok"
+
+        it "reports connection loss promptly, waking a command already in flight" $
+            withServer
+                ( \socket frames -> do
+                    send socket greeting
+                    _abandoned <- recv frames
+                    closeSock socket
+                )
+                \port -> do
+                    outcome <-
+                        timeout 2_000_000 . try $
+                            runMarionetteTWith
+                                "127.0.0.1"
+                                port
+                                testCommandTimeout
+                                (sendCommand @_ @Aeson.Value "abandoned")
+
+                    outcome `shouldSatisfy` \case
+                        Just (Left SocketClosed) -> True
+                        _ -> False
+
+        it "surfaces a server-reported Error rather than a transport failure" $
+            withServer
+                ( \socket frames -> do
+                    send socket greeting
+                    command <- recv frames
+                    reply socket command $
+                        Left Error{error = "no such element", message = "nope", stacktrace = ""}
+                )
+                \port -> do
+                    outcome <-
+                        try $
+                            runMarionetteTWith
+                                "127.0.0.1"
+                                port
+                                testCommandTimeout
+                                (sendCommand @_ @Aeson.Value "find")
+
+                    outcome `shouldSatisfy` \case
+                        Left Error{message = "nope"} -> True
+                        _ -> False
+
+        it "discards a reply that arrives after its command already timed out" $
+            withServer
+                ( \socket frames -> do
+                    send socket greeting
+                    slow <- recv frames
+                    echoed <- recv frames -- only received once the client gives up on "slow"
+                    reply socket slow $ Right (Aeson.String "too late")
+                    reply socket echoed $ Right (Aeson.String "ok")
+                )
+                \port ->
+                    runMarionetteTWith "127.0.0.1" port testCommandTimeout do
+                        slow <- try $ sendCommand @_ @Aeson.Value "slow"
+                        slow `shouldSatisfy` \case
+                            Left MarionetteTimeout{} -> True
+                            _ -> False
+                        sendCommand "echo" `shouldReturn` Aeson.String "ok"
diff --git a/test/Main.hs b/test/Main.hs
--- a/test/Main.hs
+++ b/test/Main.hs
@@ -1,18 +1,20 @@
-{-# OPTIONS_GHC -Wno-orphans #-}
-
 module Main where
 
-import Control.Concurrent (forkIO, killThread)
-import Control.Exception (bracket)
+import Control.Exception (Exception, bracket, throwIO)
 import Data.Aeson (toJSON)
 import Data.ByteString qualified as ByteString
 import Data.Functor (void)
+import Data.Maybe (isNothing)
 import Data.Text (Text)
 import Data.Text qualified as Text
 import Lucid
 import Network.HTTP.Types (status200)
+import Network.Socket (PortNumber)
 import Network.Wai (Application, rawPathInfo, responseLBS)
-import Network.Wai.Handler.Warp (run)
+import Network.Wai.Handler.Warp (Port, testWithApplication)
+import System.Directory (doesFileExist)
+import System.FilePath ((</>))
+import System.IO.Temp (withSystemTempDirectory)
 import System.Process.Typed
     ( checkExitCode
     , nullStream
@@ -21,13 +23,17 @@
     , setStdout
     , startProcess
     )
-import Test.Hspec (describe, hspec, it)
+import Test.Hspec (Spec, describe, hspec)
+import Test.Hspec qualified as Hspec
 import Test.Hspec.Expectations.Lifted
-import Test.Marionette
+import Test.Marionette hiding (navigate)
+import Test.Marionette qualified as Marionette
 import Test.Marionette.Cookie qualified as Cookie
+import Test.Marionette.Key qualified as Key
 import Test.Marionette.Rect qualified as Rect
 import Test.Marionette.Timeouts qualified as Timeouts
 import Test.Marionette.WebAuthn qualified as WebAuthn
+import UnliftIO.Retry (constantDelay, limitRetriesByCumulativeDelay, retrying)
 import Prelude hiding (print)
 
 page :: Text -> Html () -> Html ()
@@ -69,6 +75,48 @@
                     button_ [id_ "alert-btn", onclick_ "alert('Hello!')"] "Alert"
                     button_ [id_ "confirm-btn", onclick_ "confirm('Sure?')"] "Confirm"
                     button_ [id_ "prompt-btn", onclick_ "prompt('Input:')"] "Prompt"
+            "/actions" ->
+                page "Actions Page" do
+                    style_
+                        "\
+                        \#hover-target { width: 100px; height: 100px; background: red; }\
+                        \#hover-target:hover { background: green; }\
+                        \#drag-source { position: absolute; top: 0; left: 0; width: 50px; height: 50px; background: blue; }\
+                        \#drop-target { position: absolute; top: 200px; left: 200px; width: 100px; height: 100px; background: yellow; }\
+                        \#scroll-container { height: 100px; overflow: auto; }\
+                        \#scroll-container div { height: 1000px; }"
+                    div_
+                        [ id_ "hover-target"
+                        , onmouseover_ "this.dataset.hovered = 'true'"
+                        , onmouseout_ "this.dataset.hovered = 'false'"
+                        ]
+                        "Hover me"
+                    div_ [id_ "drag-source"] "Drag"
+                    div_ [id_ "drop-target"] "Drop"
+                    button_ [id_ "shift-click-btn", onclick_ "this.dataset.shift = event.shiftKey"] "Click"
+                    div_ [id_ "scroll-container"] (div_ mempty "tall content")
+                    script_
+                        "\
+                        \(function () {\
+                        \  const source = document.getElementById('drag-source');\
+                        \  const target = document.getElementById('drop-target');\
+                        \  let dragging = false;\
+                        \  source.addEventListener('pointerdown', () => { dragging = true; });\
+                        \  document.addEventListener('pointermove', (e) => {\
+                        \    if (!dragging) return;\
+                        \    source.style.left = (e.clientX - 25) + 'px';\
+                        \    source.style.top = (e.clientY - 25) + 'px';\
+                        \  });\
+                        \  document.addEventListener('pointerup', () => {\
+                        \    if (!dragging) return;\
+                        \    dragging = false;\
+                        \    const sr = source.getBoundingClientRect();\
+                        \    const tr = target.getBoundingClientRect();\
+                        \    const overlap = sr.left < tr.right && sr.right > tr.left\
+                        \      && sr.top < tr.bottom && sr.bottom > tr.top;\
+                        \    target.dataset.dropped = overlap ? 'true' : 'false';\
+                        \  });\
+                        \})();"
             _ ->
                 page "Marionette Test" do
                     h1_ [id_ "heading"] "Hello, Marionette!"
@@ -77,66 +125,86 @@
                     div_ [id_ "parent"] do
                         span_ [id_ "child"] "Child element"
 
-withTestServer :: IO a -> IO a
-withTestServer = bracket (forkIO $ run 8080 app) killThread . const
+newtype MarionetteDidNotStart = MarionetteDidNotStart FilePath
+    deriving stock (Show)
+    deriving anyclass (Exception)
 
-withFirefox :: IO a -> IO a
-withFirefox =
-    bracket
-        ( startProcess
-            . setStdout nullStream
-            . setStderr nullStream
-            . proc "firefox"
-            $ [ "--marionette"
-              , "--headless"
-              , "-remote-allow-system-access"
-              ]
-        )
-        ( \process -> do
-            runMarionetteT $ newSession >> quit
-            checkExitCode process
-        )
-        . const
+awaitMarionettePort :: FilePath -> IO PortNumber
+awaitMarionettePort profile = do
+    port <-
+        retrying
+            (limitRetriesByCumulativeDelay 5_000_000 $ constantDelay 100_000)
+            (const $ pure . isNothing)
+            (const poll)
+    maybe (throwIO $ MarionetteDidNotStart activePortPath) pure port
+  where
+    activePortPath = profile </> "MarionetteActivePort"
+    poll =
+        doesFileExist activePortPath >>= \case
+            True -> Just . read <$> readFile activePortPath
+            False -> pure Nothing
 
-run' :: (HasCallStack) => MarionetteT IO () -> IO ()
-run' action = runMarionetteT do
-    newSession
-    navigate "http://localhost:8080/"
-    action
-    deleteSession
+withFirefox :: (PortNumber -> IO a) -> IO a
+withFirefox action =
+    withSystemTempDirectory "marionette-test-profile" \profile -> do
+        writeFile (profile </> "user.js") "user_pref(\"marionette.port\", 0);\n"
+        bracket
+            ( do
+                process <-
+                    startProcess
+                        . setStdout nullStream
+                        . setStderr nullStream
+                        . proc "firefox"
+                        $ [ "--profile"
+                          , profile
+                          , "--marionette"
+                          , "--headless"
+                          , "-remote-allow-system-access"
+                          ]
+                port <- awaitMarionettePort profile
+                pure (process, port)
+            )
+            ( \(process, port) -> do
+                runMarionetteTWith "localhost" port defaultCommandTimeout $ newSession >> quit
+                checkExitCode process
+            )
+            (action . snd)
 
 main :: IO ()
-main = withTestServer . withFirefox . hspec $ do
+main = testWithApplication (pure app) $ (withFirefox . (hspec .)) . spec
+
+spec :: Port -> PortNumber -> Spec
+spec httpPort marionettePort = describe "Marionette" do
     describe "Session" do
-        it "can create and delete a session" . run' $ do
+        it "can create and delete a session" do
             deleteSession
             newSession
 
     describe "Navigation" do
-        it "navigates to a URL" . run' $ getCurrentURL `shouldReturn` "http://localhost:8080/"
+        it "navigates to a URL" $ getCurrentURL `shouldReturn` url "/"
 
-        it "can go back and forward" . run' $ do
-            navigate "http://localhost:8080/target"
+        it "can go back and forward" do
+            navigate "/target"
             back
-            getCurrentURL `shouldReturn` "http://localhost:8080/"
+            getCurrentURL `shouldReturn` url "/"
             forward
-            getCurrentURL `shouldReturn` "http://localhost:8080/target"
+            getCurrentURL `shouldReturn` url "/target"
 
-        it "can refresh" . run' $ do
+        it "can refresh" do
             refresh
-            getCurrentURL `shouldReturn` "http://localhost:8080/"
+            getCurrentURL `shouldReturn` url "/"
 
-        it "getTitle returns page title" . run' $ getTitle `shouldReturn` "Marionette Test"
+        it "getTitle returns page title" $ getTitle `shouldReturn` "Marionette Test"
 
-        it "getPageSource returns HTML" . run' $ do
+        it "getPageSource returns HTML" do
             source <- getPageSource
             source `shouldSatisfy` Text.isInfixOf "Hello, Marionette!"
 
-        it "getCurrentURL returns current URL" . run' $
-            getCurrentURL `shouldReturn` "http://localhost:8080/"
+        it "getCurrentURL returns current URL" $
+            getCurrentURL `shouldReturn` url "/"
 
     describe "Timeouts" do
-        it "setTimeouts / getTimeouts roundtrip" . run' $ do
+        it "setTimeouts / getTimeouts roundtrip" do
             let t =
                     Timeouts
                         { script = Just 5000
@@ -147,20 +215,20 @@
             getTimeouts `shouldReturn` t
 
     describe "Window" do
-        it "getWindowHandle returns a handle" . run' $ do
+        it "getWindowHandle returns a handle" do
             handle <- getWindowHandle
             handle `shouldSatisfy` not . null . show
 
-        it "getWindowHandles returns at least one handle" . run' $ do
+        it "getWindowHandles returns at least one handle" do
             handles <- getWindowHandles
             handles `shouldSatisfy` not . null
 
-        it "getWindowRect returns a rect" . run' $ do
+        it "getWindowRect returns a rect" do
             Rect{..} <- getWindowRect
             width `shouldSatisfy` (> 0)
             height `shouldSatisfy` (> 0)
 
-        it "setWindowRect / getWindowRect roundtrip" . run' $ do
+        it "setWindowRect / getWindowRect roundtrip" do
             let r =
                     Rect
                         { x = 0
@@ -171,18 +239,18 @@
             setWindowRect r
             getWindowRect `shouldReturn` r
 
-        it "maximizeWindow does not throw" $ run' maximizeWindow
-        it "minimizeWindow does not throw" $ run' minimizeWindow
-        it "fullscreenWindow does not throw" $ run' fullscreenWindow
+        it "maximizeWindow does not throw" maximizeWindow
+        it "minimizeWindow does not throw" minimizeWindow
+        it "fullscreenWindow does not throw" fullscreenWindow
 
-        it "newTab opens a new window handle" . run' $ do
+        it "newTab opens a new window handle" do
             before <- getWindowHandles
             NewWindowResult{..} <- newTab
             -- newWindowType `shouldBe` Tab
             after <- getWindowHandles
             after `shouldBe` before <> [newWindowHandle]
 
-        it "newWindow opens a new window handle" . run' $ do
+        it "newWindow opens a new window handle" do
             before <- getWindowHandles
             NewWindowResult{..} <- newTab
             -- This does not seem to work
@@ -190,7 +258,7 @@
             after <- getWindowHandles
             after `shouldBe` before <> [newWindowHandle]
 
-        it "switchToWindow and closeWindow" . run' $ do
+        it "switchToWindow and closeWindow" do
             original <- getWindowHandle
             NewWindowResult{..} <- newTab
             switchToWindow newWindowHandle
@@ -200,141 +268,141 @@
             getWindowHandle `shouldReturn` original
 
     describe "Element finding" do
-        it "findElement by id" . run' $ do
+        it "findElement by id" do
             el <- findElement (ById "heading")
             getElementText el `shouldReturn` "Hello, Marionette!"
 
-        it "findElement by class" . run' $ do
+        it "findElement by class" do
             el <- findElement (ByClass "content")
             getElementText el `shouldReturn` "Test paragraph"
 
-        it "findElement by tag" . run' $ do
+        it "findElement by tag" do
             el <- findElement (ByTag "h1")
             getElementText el `shouldReturn` "Hello, Marionette!"
 
-        it "findElement by CSS selector" . run' $ do
+        it "findElement by CSS selector" do
             el <- findElement (ByCSS "#heading")
             getElementText el `shouldReturn` "Hello, Marionette!"
 
-        it "findElement by XPath" . run' $ do
+        it "findElement by XPath" do
             el <- findElement (ByXPath "//h1[@id='heading']")
             getElementText el `shouldReturn` "Hello, Marionette!"
 
-        it "findElements returns multiple elements" . run' $ do
+        it "findElements returns multiple elements" do
             els <- findElements (ByClass "content")
             length els `shouldBe` 2
 
-        it "findElementFrom finds child within parent" . run' $ do
+        it "findElementFrom finds child within parent" do
             parent <- findElement (ById "parent")
             child <- findElementFrom parent (ById "child")
             getElementText child `shouldReturn` "Child element"
 
-        it "findElementsFrom finds children within parent" . run' $ do
+        it "findElementsFrom finds children within parent" do
             parent <- findElement (ById "parent")
             children :: [Element] <- findElementsFrom parent (ByTag "span")
             length children `shouldBe` 1
 
-        it "findElement by link text" . run' $ do
-            navigate "http://localhost:8080/link"
+        it "findElement by link text" do
+            navigate "/link"
             el <- findElement (ByLinkText "Click me")
             getElementText el `shouldReturn` "Click me"
 
-        it "findElement by partial link text" . run' $ do
-            navigate "http://localhost:8080/link"
+        it "findElement by partial link text" do
+            navigate "/link"
             el <- findElement (ByPartialLinkText "Click here")
             text <- getElementText el
             text `shouldSatisfy` Text.isInfixOf "Click here"
 
     describe "Element properties" do
-        it "getElementAttribute" . run' $ do
+        it "getElementAttribute" do
             el <- findElement (ById "para")
             getElementAttribute "class" el `shouldReturn` Just "content"
 
-        it "getElementProperty" . run' $ do
+        it "getElementProperty" do
             el <- findElement (ById "para")
             getElementProperty el "id" `shouldReturn` Just "para"
 
-        it "getElementTagName" . run' $ do
+        it "getElementTagName" do
             el <- findElement (ById "heading")
             getElementTagName el `shouldReturn` "h1"
 
-        it "getElementRect" . run' $ do
+        it "getElementRect" do
             el <- findElement (ById "heading")
             Rect{..} <- getElementRect el
             width `shouldSatisfy` (> 0)
 
-        it "getElementCSSValue" . run' $ do
+        it "getElementCSSValue" do
             el <- findElement (ById "heading")
             val <- getElementCSSValue el "display"
             val `shouldSatisfy` not . null . show
 
-        it "getComputedRole" . run' $ do
+        it "getComputedRole" do
             el <- findElement (ById "heading")
             role <- getComputedRole el
             role `shouldSatisfy` not . Text.null
 
-        it "getComputedLabel" . run' $ do
-            navigate "http://localhost:8080/form"
+        it "getComputedLabel" do
+            navigate "/form"
             el <- findElement (ById "submit")
             label <- getComputedLabel el
             label `shouldSatisfy` not . Text.null
 
-        it "isElementDisplayed" . run' $ do
-            navigate "http://localhost:8080/"
+        it "isElementDisplayed" do
+            navigate "/"
             el <- findElement (ById "heading")
             isElementDisplayed el `shouldReturn` True
 
-        it "isElementEnabled" . run' $ do
-            navigate "http://localhost:8080/form"
+        it "isElementEnabled" do
+            navigate "/form"
             el <- findElement (ById "text-input")
             isElementEnabled el `shouldReturn` True
 
-        it "isElementSelected for unchecked checkbox" . run' $ do
-            navigate "http://localhost:8080/form"
+        it "isElementSelected for unchecked checkbox" do
+            navigate "/form"
             el <- findElement (ById "checkbox")
             isElementSelected el `shouldReturn` False
 
-        it "getActiveElement does not throw" . run' . void $ getActiveElement
+        it "getActiveElement does not throw" $ void getActiveElement
 
     describe "Element interaction" do
-        it "elementClick navigates via link" . run' $ do
-            navigate "http://localhost:8080/link"
+        it "elementClick navigates via link" do
+            navigate "/link"
             el <- findElement (ById "link")
             elementClick el
-            getCurrentURL `shouldReturn` "http://localhost:8080/target"
+            getCurrentURL `shouldReturn` url "/target"
 
-        it "elementSendKeys fills input" . run' $ do
-            navigate "http://localhost:8080/form"
+        it "elementSendKeys fills input" do
+            navigate "/form"
             el <- findElement (ById "text-input")
             elementSendKeys el "hello"
             getElementProperty el "value" `shouldReturn` Just "hello"
 
-        it "elementClear clears input" . run' $ do
-            navigate "http://localhost:8080/form"
+        it "elementClear clears input" do
+            navigate "/form"
             el <- findElement (ById "text-input")
             elementSendKeys el "hello"
             elementClear el
             getElementProperty el "value" `shouldReturn` Just ""
 
     describe "Script execution" do
-        it "executeScript returns a value" . run' $ do
+        it "executeScript returns a value" $
             executeScript "return 1 + 1" [] `shouldReturn` (2 :: Int)
 
-        it "executeScript can access elements" . run' $ do
-            navigate "http://localhost:8080/"
+        it "executeScript can access elements" do
+            navigate "/"
             executeScript
                 "return document.getElementById(arguments[0]).textContent"
                 [toJSON @Text "heading"]
                 `shouldReturn` ("Hello, Marionette!" :: Text)
 
-        it "executeAsyncScript returns a value" . run' $ do
+        it "executeAsyncScript returns a value" do
             executeAsyncScript @_ @_ @Int
                 "const callback = arguments[arguments.length - 1]; setTimeout(() => callback(arguments[0]), 100)"
                 [toJSON @Int 42]
                 `shouldReturn` Just 42
 
     describe "Cookies" do
-        it "addCookie / getCookies roundtrip" . run' $ do
+        it "addCookie / getCookies roundtrip" do
             deleteAllCookies
             let cookie =
                     Cookie
@@ -350,7 +418,7 @@
             cookies <- getCookies
             cookies `shouldSatisfy` any \c -> Cookie.name c == "test"
 
-        it "deleteCookie removes a cookie" . run' $ do
+        it "deleteCookie removes a cookie" do
             deleteAllCookies
             let cookie =
                     Cookie
@@ -367,67 +435,67 @@
             cookies <- getCookies
             cookies `shouldNotSatisfy` any \c -> Cookie.name c == "test"
 
-        it "deleteAllCookies removes all cookies" . run' $ do
+        it "deleteAllCookies removes all cookies" do
             deleteAllCookies
             getCookies `shouldReturn` []
 
     describe "Alerts" do
-        it "acceptAlert dismisses an alert" . run' $ do
-            navigate "http://localhost:8080/alert"
+        it "acceptAlert dismisses an alert" do
+            navigate "/alert"
             el <- findElement (ById "alert-btn")
             elementClick el
             getAlertText `shouldReturn` "Hello!"
             acceptAlert
 
-        it "dismissAlert dismisses a confirm dialog" . run' $ do
-            navigate "http://localhost:8080/alert"
+        it "dismissAlert dismisses a confirm dialog" do
+            navigate "/alert"
             el <- findElement (ById "confirm-btn")
             elementClick el
             dismissAlert
 
-        it "sendAlertText fills a prompt" . run' $ do
-            navigate "http://localhost:8080/alert"
+        it "sendAlertText fills a prompt" do
+            navigate "/alert"
             el <- findElement (ById "prompt-btn")
             elementClick el
             sendAlertText "my input"
             acceptAlert
 
     describe "Frames" do
-        it "switchToParentFrame does not throw" . run' $ switchToParentFrame
+        it "switchToParentFrame does not throw" switchToParentFrame
 
     describe "Context" do
-        it "getContext returns a context" . run' $ do
+        it "getContext returns a context" do
             ctx <- getContext
             ctx `shouldSatisfy` (`elem` [minBound .. maxBound])
 
-        it "setContext / getContext roundtrip" . run' $ do
+        it "setContext / getContext roundtrip" do
             setContext ContentContext
             getContext `shouldReturn` ContentContext
             setContext ChromeContext
             getContext `shouldReturn` ChromeContext
 
     describe "Shadow DOM" do
-        it "getShadowRoot / findElementFromShadowRoot" . run' $ do
-            navigate "http://localhost:8080/shadow"
+        it "getShadowRoot / findElementFromShadowRoot" do
+            navigate "/shadow"
             host <- findElement (ById "host")
             shadow <- getShadowRoot host
             el <- findElementFromShadowRoot shadow (ByCSS "#shadow-p")
             getElementText el `shouldReturn` "Shadow content"
 
-        it "findElementsFromShadowRoot" . run' $ do
-            navigate "http://localhost:8080/shadow"
+        it "findElementsFromShadowRoot" do
+            navigate "/shadow"
             host <- findElement (ById "host")
             shadow <- getShadowRoot host
             els <- findElementsFromShadowRoot shadow (ByCSS "p")
             length els `shouldBe` 1
 
     describe "Screenshots" do
-        it "takeScreenshot returns non-empty bytes" . run' $ do
+        it "takeScreenshot returns non-empty bytes" do
             bytes <- takeScreenshot
             ByteString.length bytes `shouldNotBe` 0
 
     describe "WebAuthn" do
-        it "addVirtualAuthenticator / getCredentials roundtrip" . run' $ do
+        it "addVirtualAuthenticator / getCredentials roundtrip" do
             let opts =
                     VirtualAuthenticator
                         { protocol = "ctap2"
@@ -443,7 +511,7 @@
             getCredentials aid `shouldReturn` []
             removeVirtualAuthenticator aid
 
-        it "setUserVerified does not throw" . run' $ do
+        it "setUserVerified does not throw" do
             let opts =
                     VirtualAuthenticator
                         { protocol = "ctap2"
@@ -460,7 +528,7 @@
             setUserVerified aid True
             removeVirtualAuthenticator aid
 
-        it "removeAllCredentials does not throw" . run' $ do
+        it "removeAllCredentials does not throw" do
             let opts =
                     VirtualAuthenticator
                         { protocol = "ctap2"
@@ -475,3 +543,79 @@
             aid <- addVirtualAuthenticator opts
             removeAllCredentials aid
             removeVirtualAuthenticator aid
+
+    describe "Actions" do
+        it "hovering dispatches mouseover/mouseout and real CSS :hover state" do
+            navigate "/actions"
+            target <- findElement (ById "hover-target")
+            getElementAttribute "data-hovered" target `shouldReturn` Nothing
+            getElementCSSValue target "background-color" `shouldReturn` Just "rgb(255, 0, 0)"
+            performActions [mouse [PointerMove 0 (FromElement target) 0 0]]
+            getElementAttribute "data-hovered" target `shouldReturn` Just "true"
+            getElementCSSValue target "background-color" `shouldReturn` Just "rgb(0, 128, 0)"
+            performActions [mouse [PointerMove 0 Viewport 0 0]]
+            getElementAttribute "data-hovered" target `shouldReturn` Just "false"
+            getElementCSSValue target "background-color" `shouldReturn` Just "rgb(255, 0, 0)"
+            releaseActions
+
+        it "drags an element onto a drop target" do
+            navigate "/actions"
+            source <- findElement (ById "drag-source")
+            target <- findElement (ById "drop-target")
+            getElementAttribute "data-dropped" target `shouldReturn` Nothing
+            performActions
+                [ mouse
+                    [ PointerMove 0 (FromElement source) 0 0
+                    , PointerDown LeftButton
+                    , PointerMove 200 (FromElement target) 0 0
+                    , PointerUp LeftButton
+                    ]
+                ]
+            getElementAttribute "data-dropped" target `shouldReturn` Just "true"
+            releaseActions
+
+        it "combines a held key and a pointer click into one gesture" do
+            navigate "/actions"
+            button <- findElement (ById "shift-click-btn")
+            performActions
+                [ keyboard [KeyDown Key.Shift]
+                , mouse
+                    [ PointerMove 0 (FromElement button) 0 0
+                    , PointerDown LeftButton
+                    , PointerUp LeftButton
+                    ]
+                ]
+            getElementAttribute "data-shift" button `shouldReturn` Just "true"
+            releaseActions
+            elementClick button
+            getElementAttribute "data-shift" button `shouldReturn` Just "false"
+
+        it "releaseActions lets go of a key held with no matching keyUp" do
+            navigate "/actions"
+            button <- findElement (ById "shift-click-btn")
+            performActions [keyboard [KeyDown Key.Shift]]
+            releaseActions
+            elementClick button
+            getElementAttribute "data-shift" button `shouldReturn` Just "false"
+
+        it "scrolls a container via a wheel action" do
+            navigate "/actions"
+            container <- findElement (ById "scroll-container")
+            (before :: Double) <- executeScript "return arguments[0].scrollTop" [toJSON container]
+            before `shouldBe` 0
+            -- A zero duration reliably does not scroll in headless Firefox,
+            -- unlike pointer moves/clicks, which work fine at duration 0.
+            performActions [wheel [Scroll 100 (FromElement container) 0 0 0 200]]
+            (after :: Double) <- executeScript "return arguments[0].scrollTop" [toJSON container]
+            after `shouldSatisfy` (> 0)
+  where
+    url path = "http://localhost:" <> Text.show httpPort <> path
+
+    navigate = Marionette.navigate . url
+
+    it :: (HasCallStack) => String -> MarionetteT IO () -> Spec
+    it label action = Hspec.it label $ runMarionetteTWith "localhost" marionettePort defaultCommandTimeout do
+        newSession
+        navigate "/"
+        action
+        deleteSession