[winswitch] [ANNOUNCE] Xpra 3.0.7: many fixes, one important

[Antoine Martin]

Hi,

There's a large number of bug fixes in this release, including a fix for
a very old bug which can cause client crashes when decoding H264
streams. There is also the usual set of clipboard and keyboard fixes,
and a smattering of platform and other minor issues (transparency, etc).

Updating is strongly recommended.

Release notes:
* fix avcodec2 race condition crash
* fix errors when re-initializing windows (ie: toggling OpenGL)
* fix deiconification error when there are system trays forwarded
* fix missing alpha channel when some windows are first shown
* fix systemd-run errors: verify it does work before trying to use it
* fix debug builds compilation error on MS Windows
* fix server crashes on SIGINT: shutdown cleanly
* fix proxy server client connection setup error hanlder
* fix file authentication handler using a default password filename
* fix directshow errors on local mingw installations
* fix opengl properties missing from server hello packet
* fix HTML5 sound-control errors when speaker forwarding is disabled
* fix HTML5 "Terminate" options wrongly enabled in "Connect" mode
* fix clipboard sharing with the MacOS shadow server
* fix MS Windows clipboard access denied errors
* fix X11 clipboard error handling: continue processing
* fix unit tests failures (clipboard, etc)
* fix bug report clipboard copy and screnshots
* fix clipboard timeouts when a client disconnects
* fix mdns cleanup done twice on server exit, causing errors
* fix malformed XSettings due to invalid color data format
* fix FreeBSD builds
* fix MS Windows packaging missing a codec DLL, Plink DLL
* fix HMAC hashes exposed, keep only valid options
* fix 'showconfig' output for boolean values set to 'auto'
* fix parsing of client display information in legacy format
* fix validation of size-hints
* fix cursor saving debug code with GTK3
* fix keyboard layout group not getting reset on client exit
* fix some empty keyboard layout group strings parsed as non-empty
* fix keyboard-sync mode not being honoured by servers
* fix keyboard raw mode
* fix missing 'perispomeni' key mapping with Python 2 servers
* add missing debug logging to keyboard mapping
* more reliable lookup of keycodes when translating (non-X11 clients)
* add missing dependency for printer forwarding on Debian
* packaging for Ubuntu Focal Fossa
* skip bundling some external test modules with binary installers
* more correct code for locating the 'Downloads' folder on MS Windows
* avoid spurious background worker warnings on exit
* make unavoidable comtypes error less scary
* add 'libreoffice' to the text mode whitelist
* library updates: Python 3.8.2, etc
* packaging workarounds for setuptools breakage


Cheers,
Antoine