diff --git a/CHANGELOG b/CHANGELOG
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,6 @@
+5.2.1
+  - Bump upper version bound for lens to 4.5. Thanks markus1189!
+
 5.2.0
   - Config structure now specifies file descriptor to use. The default is stdInput and stdOutput
     file descriptors. Previously Vty used stdInput for input and the follow code for output:
@@ -88,88 +91,88 @@
       - test/benchmark.hs
 
 4.7.0.0
-    * API changes:
-       * Added Graphics.Vty.Image.crop: Ensure an image is no larger than the specified size.
-       * Added Graphics.Vty.Image.pad: Ensure an image is no smaller than the specified size.
-       * Added Graphics.Vty.Image.translate: Offset an image.
-    * Thanks Ben Boeckel <MathStuf@gmail.com> for these features.
+    - API changes:
+       - Added Graphics.Vty.Image.crop: Ensure an image is no larger than the specified size.
+       - Added Graphics.Vty.Image.pad: Ensure an image is no smaller than the specified size.
+       - Added Graphics.Vty.Image.translate: Offset an image.
+    - Thanks Ben Boeckel <MathStuf@gmail.com> for these features.
 
 4.3.0.0
 
 4.2.1.0
-    * API changes:
-        * Attr record accessor fore_color changed to attr_fore_color
-        * Attr record accessor back_color changed to attr_back_color
-        * Attr record accessor style changed to attr_style
-        * Added an "inline" display attribute changing DSL:
-            * put_attr_change applies a display attribute change immediately to a terminal
-            * For instance, can be used to change the display attrbiutes of text output via putStrLn
+    - API changes:
+        - Attr record accessor fore_color changed to attr_fore_color
+        - Attr record accessor back_color changed to attr_back_color
+        - Attr record accessor style changed to attr_style
+        - Added an "inline" display attribute changing DSL:
+            - put_attr_change applies a display attribute change immediately to a terminal
+            - For instance, can be used to change the display attrbiutes of text output via putStrLn
               and putStr. EX: "put_attr_change $ back_color red" will set the
               background color to red. 
-            * Changes do not apply to a Picture output via output_picture. 
-            * See Graphics.Vty.Inline
-        * Moved all IO actions into any monad an instance of MonadIO
+            - Changes do not apply to a Picture output via output_picture. 
+            - See Graphics.Vty.Inline
+        - Moved all IO actions into any monad an instance of MonadIO
 
 4.0.0.1
-    * binding for mk_wcswidth was incorrect. Most platforms just magically worked due to
+    - binding for mk_wcswidth was incorrect. Most platforms just magically worked due to
       coincidence.
 
 4.0.0
-    * API changes:
-        * "getSize" has been removed. Use "terminal vty >>= display_bounds" where "vty" is an
+    - API changes:
+        - "getSize" has been removed. Use "terminal vty >>= display_bounds" where "vty" is an
           instance of the Vty data structure.
-        * added a "terminal" field to the Vty data structure. Accesses the TerminalHandle associated
+        - added a "terminal" field to the Vty data structure. Accesses the TerminalHandle associated
           with the Vty instance.
-        * Graphics.Vty.Types has undergone a number of changes. Summary:
-          * Partitioned into Graphics.Vty.Attributes for display attributes. Graphics.Vty.Image for
+        - Graphics.Vty.Types has undergone a number of changes. Summary:
+          - Partitioned into Graphics.Vty.Attributes for display attributes. Graphics.Vty.Image for
             image combinators. Graphics.Vty.Picture for final picture construction.
-        * Graphics.Vty.Attributes:
-          * "setFG" and "setBG" are now "with_fore_color" and "with_back_color"
-          * All other "set.." equations similarly replaced.
-          * "attr" is now "def_attr", short for "default display attributes" Also added a
+        - Graphics.Vty.Attributes:
+          - "setFG" and "setBG" are now "with_fore_color" and "with_back_color"
+          - All other "set.." equations similarly replaced.
+          - "attr" is now "def_attr", short for "default display attributes" Also added a
             "current_attr" for "currently applied display attributes"
-        * Graphics.Vty.Image:
-          * "horzcat" is now "horiz_cat"
-          * "vertcat" is now "vert_cat"
-          * "renderBS" is now "utf8_bytestring"
-          * "renderChar" is now "char"
-          * "renderFill" is now "char_fill"
-          * added a "utf8_string" and "string" (AKA "iso_10464_string") for UTF-8 encoded Strings
+        - Graphics.Vty.Image:
+          - "horzcat" is now "horiz_cat"
+          - "vertcat" is now "vert_cat"
+          - "renderBS" is now "utf8_bytestring"
+          - "renderChar" is now "char"
+          - "renderFill" is now "char_fill"
+          - added a "utf8_string" and "string" (AKA "iso_10464_string") for UTF-8 encoded Strings
             and ISO-10464 encoded Strings. String literals in GHC have an ISO-10464 runtime
             representation.
-        * Graphics.Vty.Picture:
-          * exports Graphics.Vty.Image
-          * "pic" is now "pic_for_image"
-          * added API for setting background fill pattern.
-    * Completely rewritten output backend.
-        * Efficient, scanline style output span generator. Has not been fully optimized, but good
+        - Graphics.Vty.Picture:
+          - exports Graphics.Vty.Image
+          - "pic" is now "pic_for_image"
+          - added API for setting background fill pattern.
+    - Completely rewritten output backend.
+        - Efficient, scanline style output span generator. Has not been fully optimized, but good
           enough.
-        * The details required to display the desired picture on a terminal are well encapsulated.
-        * Terminfo based display terminal implementation. With specialized derivitives for xterm,
+        - The details required to display the desired picture on a terminal are well encapsulated.
+        - Terminfo based display terminal implementation. With specialized derivitives for xterm,
           Terminal.app, and iTerm.app. 
-            * Attempts to robustly handle even terminals that don't support all display attributes.
-            * I've tested the following terminals with success: iTerm.app, Terminal.app, xterm,
+            - Attempts to robustly handle even terminals that don't support all display attributes.
+            - I've tested the following terminals with success: iTerm.app, Terminal.app, xterm,
               rxvt, mlterm, Eterm, gnome-terminal, konsole, screen, linux vty. Hopefully you will be
               as successfull. 
-        * Improved unicode support. Double wide characters will display as expected.
-    * 256 color support. See Graphics.Vty.Attributes.Color240. The actual output color is adjusted
+        - Improved unicode support. Double wide characters will display as expected.
+    - 256 color support. See Graphics.Vty.Attributes.Color240. The actual output color is adjusted
       according to the number of colors the terminal supports.
-    * The Graphics.Vty.Image combinators no longer require matching dimensions to arguments.
+    - The Graphics.Vty.Image combinators no longer require matching dimensions to arguments.
       Unspecified areas are filled in with a user-customizable background pattern. See
       Graphics.Vty.Picture.
-    * output images are always cropped to display size.
-    * Significant code coverage by QuickCheck tests. An interactive test for those final properties
+    - output images are always cropped to display size.
+    - Significant code coverage by QuickCheck tests. An interactive test for those final properties
       that couldn't be automatically verified.
 
     issues resolved:
-        * "gnome terminal displays non-basic attributes as strikethrough"
-            * http://trac.haskell.org/vty/ticket/14
-        * "Multi-byte characters are not displayed correctly on update"
-            * http://trac.haskell.org/vty/ticket/10
-        * "Redraw does not handle rendering a line that extends beyond screen width characters" 
-            * http://trac.haskell.org/vty/ticket/13
-        * "The <|> and <-> combinators should be more forgiving of mismatched dimensions" 
-            * http://trac.haskell.org/vty/ticket/9
-        * "256-color support" 
-            * http://trac.haskell.org/vty/ticket/19
+        - "gnome terminal displays non-basic attributes as strikethrough"
+            - http://trac.haskell.org/vty/ticket/14
+        - "Multi-byte characters are not displayed correctly on update"
+            - http://trac.haskell.org/vty/ticket/10
+        - "Redraw does not handle rendering a line that extends beyond screen width characters" 
+            - http://trac.haskell.org/vty/ticket/13
+        - "The <|> and <-> combinators should be more forgiving of mismatched dimensions" 
+            - http://trac.haskell.org/vty/ticket/9
+        - "256-color support" 
+            - http://trac.haskell.org/vty/ticket/19
 
diff --git a/src/Graphics/Vty/Config.hs b/src/Graphics/Vty/Config.hs
--- a/src/Graphics/Vty/Config.hs
+++ b/src/Graphics/Vty/Config.hs
@@ -51,7 +51,7 @@
 -- @
 --  map _       \"\\ESC[B\"    KUp   []
 --  map _       \"\\ESC[1;3B\" KDown [MAlt]
---  map "xterm" \"\\ESC[D\"    KLeft []
+--  map \"xterm\" \"\\ESC[D\"    KLeft []
 -- @
 --
 -- Then the bytes @\"\\ESC[B\"@ will result in the KUp event on all terminals. The bytes
diff --git a/vty.cabal b/vty.cabal
--- a/vty.cabal
+++ b/vty.cabal
@@ -1,5 +1,5 @@
 name:                vty
-version:             5.2.0
+version:             5.2.1
 license:             BSD3
 license-file:        LICENSE
 author:              AUTHORS
@@ -50,7 +50,7 @@
                        deepseq >= 1.1 && < 1.4,
                        directory,
                        filepath >= 1.0 && < 2.0,
-                       lens >= 3.9.0.2 && < 4.4,
+                       lens >= 3.9.0.2 && < 4.5,
                        -- required for nice installation with yi
                        hashable >= 1.2,
                        mtl >= 1.1.1.0 && < 2.3,
