Tcl/Tk 8.6.12 Release Announcement
November 5, 2021

The Tcl Core Team is pleased to announce the 8.6.12 releases of the Tcl
dynamic language and the Tk toolkit.  This is the twelfth patch release
of Tcl/Tk 8.6.  More details can be found below.  We would like to
express our gratitude to all those who submit bug reports and patches.
This information is invaluable in enabling us to identify and eliminate
problems in the core.

Where to get the new releases:
------------------------------

Tcl/Tk 8.6.12 sources are freely available as open source from the
Tcl Developer Xchange web site at:

        http://www.tcl-lang.org/software/tcltk/8.6.html

This web page also contains additional information about the releases,
including new features and notes about installing and compiling the
releases.  Sources are always available from the Tcl SourceForge
project's file distribution area:

        http://sourceforge.net/projects/tcl/files/

This distribution is source code only.  We keep links to some third
parties offering pre-built binaries for various systems here:

        http://www.tcl-lang.org/software/tcltk/bindist.html

For additional information:
---------------------------

Please visit the Tcl Developer Xchange web site:

        http://www.tcl-lang.org/

This site contains a variety of information about Tcl/Tk in general, the
core Tcl and Tk distributions, Tcl development tools, and much more.

Summary of Changes since Tcl/Tk 8.6.11:
--------------------------------------

This is a patch release, so it primarily includes bug fixes and corrections
to erratic behavior.  Highlighted changes are noted below.  The changes file
at the root of the source tree contains a more complete list.  The Timelines
of all changes are online.

	http://core.tcl-lang.org/tcl/
	http://core.tcl-lang.org/tk/

   * Tk compatibility with Mac OSX, including Monterey
      - Make use of a backing CALayer to fix rendering issues
      - Respect the key repeat system setting
      - File dialogs on Monterey
      - Clarify use of icons in [tk_messageBox]
      - Improved support of pixel formats
      - Avoid multiple button events during window activation
      - Raise Tk window when exposed by Mission Control

   * [TIP 608] New virtual event <<TkWorldChanged>>

   * New keycodes:	CodeInput, SingleCandidate, MultipleCandidate,
			PreviousCandidate

   * Keycode portability:	OE, oe, Ydiaeresis

   * New support for POSIX error: EILSEQ 

   * Unix tty channels now tolerate EINTR
        *** POTENTIAL INCOMPATIBILITY ***

   * Try to restore Tcl's [update] command when Tk is unloaded.

   * Addressed build tool security issue raised in CVE-2021-35331.

   * Fix crashes or hangs in...
      - Mac window event when non-Tk windows go full screen
      - Windows loading of the Phaistos font.
      - embeded window destruction when container toplevel is reused
      - Mac menu label contains non-BMP character
      - Mac use of a dead key as menu accelerator (e.g. command-acute)
      - [tkwait variable] with race in variable destruction
      - [clipboard get] with data in invalid encoding
      - Tcl_PutEnv() called from main() on Windows
      - ensemble rewrite machinery (see namespace-42.11)

   * TkpDrawAngledCharsInContext leaked a CGColor.

   * Adapt some string operations for Emoji

   * Repair EIAS violation in [concat foo [list #]]

   * Package initialization order in wish using static packages

   * Make Xft usage thread safe.

   * Failure when a [proc] argument name is computed, not literal

   * Peer text cursor motion (see textDisp-11.22)

   * Support for Unicode 14

   * tzdata updated to Olson's tzdata2021e

   * Updated bundled packages
      - Itcl 4.2.2
      - sqlite3 3.36.0
      - Thread 2.8.7
      - TDBC* 1.1.3
      - dde 1.4.4 - Tcl 9 installation compatibility
      - platform 1.0.18 - Big Sur and Monterey support

--
Tcl Core Team and Maintainers
Don Porter, Tcl Core Release Manager