MKVToolNix GUI: removed the keyboard shortcuts for switching between the different tools (e.g. via the `-ui-language` command-line option or via the GUI's preferences) did not work on Linux & Unix if the `LANGUAGE` environment variable was set and didn't include the desired language all: selecting the program's language (e.g. mkvpropedit: added support for the 'video projection' track header attributes. mkvpropedit: added support for editing the video colour attributes. mkvinfo: added support for the 'video projection' track header attributes. mkvmerge: added support for the 'video projection' track header attributes.

Additionally, push buttons to move them up & down are shown if the corresponding option is enabled in the preferences MKVToolNix GUI: job queue: selected jobs can now be move up and down by pressing the `Ctrl+Up` and `Ctrl+Down` keys. MKVToolNix GUI: header editor: added support for the 'video projection' track header attributes.

MKVToolNix GUI: header editor: added support for editing the video colour attributes. If enabled, only source files containing video tracks will be used for setting the destination file name. MKVToolNix GUI: multiplex tool: added an option in the preferences on 'Multiplexer' → 'Output' labeled 'Only use the first source file that contains a video track'. It will also force setting the destination file name once if automatic destination file name generation is turned off in the preferences. It will force the GUI to consider the selected file to be the reference for automatically setting the file name, no matter which file was originally added as the first file. MKVToolNix GUI: multiplex tool: added a new entry to the 'source files' context menu labeled 'Set destination file name from selected file's name'.

Due to this change libEBML v1.3.5 is now required the `TagLanguage` element with a value of `und` if it isn't present in its `SimpleTag` parent). mkvmerge, mkvpropedit, GUI's header and chapter editors: the programs will no longer add most missing Matroska elements that are mandatory but have a default value in the Matroska specification (e.g.

For mac instal MKVToolnix 81.0.0