[http://sf.net/projects/tcl/files/Tcl/8.6.6/tcltk-release-notes-8.6.6.txt/view%|%Released]
July 27, 2016.

**Tcl Changes**

Updated to use [Unicode 9.0].

***Changes to Tcl Commands***

****Expanded Syntax / New Options****

****Modified Behavior****

   * [file] support for more Windows filesystem conventions
   * [namespace upvar] ignores custom resolvers
   * [namespace delete] now has linear performance in size of namespace

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**Tk Changes**
***Changes to Tk Commands***

****Expanded Syntax / New Options****

   * [TIP] 443: More configuration options for [text] tags
   * [TIP] 446: More information out of [text] undo mechanism

***Look and Feel***

   * Appearance fixes for [OSX]/Aqua

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**Changes to Bundled Packages**
***Updated packages***

<<categories>> Documentation | Changes in Tcl/Tk