MKVToolNix 68.0.0 (64-bit)

What's new in this version:

- New features and enhancements:
- mkvmerge: HDMV PGS subtitles: mkvmerge now tries to detect bogus timestamps (where the current timestamp is two hours or more after the previous timestamp) & correct them to something more sensible (1s after the previous timestamp). That way one bogus timestamp cannot cause the rest of the frames to not be interleaved properly with the other audio & video packets.
- mkvmerge: added colour information, colour mastering meta information & video projection information properties to the JSON identification format. The properties are reported for container types for which mkvmerge supports reading them (Matroska & MP4). The JSON identification format version number has been bumped to v15
- MKVToolNix GUI: multiplexer: added controls for all the video colour information & the video projection information

Fixed:
- mkvmerge: SRT reader: entries with a duration of 0 or less will now be skipped
- mkvpropedit, MKVToolNix GUI's chapter & header editors: fixed an invalid memory access when trying to update existing Matroska files whose EBML Head
- element had a "size" field length of eight bytes, and where rewriting said
- element would shrink the element by one byte. Files created by gstreamer fit
- the first part whereas the second depends on the changes requested by the user.
- mkvpropedit, MKVToolNix GUI's chapter & header editors: fixed the programs not handling having to remove EBML void elements at the end of the file correctly and consequently aborting.
- MKVToolNix GUI: the GUI now uses almost all SVG icons, allowing proper scaling even for scaling factors such as 125%
- MKVToolNix GUI: when compiled with Qt 5 the character set of INI files is forced to UTF-8 in order to fix reading INI files written by a version compiled with Qt 6

Build system changes:
- Qt's SVG library is now required