MKVToolNix 92.0 “Everglow”

# Version 92.0 "Everglow" 2025-04-26

## New features and enhancements

* mkvmerge: FLAC reader: pictures embedded into the FLAC file were already
  handled as attachments, but they were left in the codec initialization data
  as well. They're now removed from the codec initialization data. See #6079.
* mkvmerge: FLAC reader: padding metadata blocks will now be removed from the
  codec initialization data. See #6079.
* mkvmerge: FLAC reader: embedded Vorbis comments will now be converted into
  Matroska comments or track/global header fields when available (e.g. `TITLE`
  will become the segment title & track's name, `LANGUAGE` will become the
  track's language). Copying of Vorbis comments that are converted into actual
  Matroska tags can be prevented with the usual options,
  e.g. `--no-track-tags`. The comments will also be removed from the codec
  initialization data. Implements #6079.
* mkvmerge, MKVToolNix GUI's chapter editor: when reading simple (OGM-style)
  chapter files & no character set is given for the file, mkvmerge will try
  UTF-8 first before falling back to the system's default encoding. Implements
  #6084.
* MKVToolNix GUI: multiplexer: the special drag & drop zones added in v91 are
  now shown by default in new installations.
* MKVToolNix GUI: in new installations the main window will now be sized at
  75% of the screen's resolution initially with a certain minimum initial
  size. This improves initial readability on high DPI screens that use screen
  scaling factors such as 150%.

## Bug fixes

* mkvmerge: Ogg reader: during identification the track tags are now reported
  properly.
* MKVToolNix GUI: multiplexer: within the "additional options", both
  track-specific ones & the global ones on the "Output" tab, it wasn't
  possible to specify empty (zero-length) arguments. With the intended syntax
  of two consecutive single or double quotation marks the empty arguments were
  simply skipped. This was fixed, and it is now possible to specify
  e.g. `--title ""` in the global "Additional options" in order to force no
  title to be written ever. Fixes #6087.

## Build system changes

* Windows build: the `packaging/windows/populate_installer_dir.sh` now expects
  the user to pass the Saxon-HE's JAR file name to be passed with the `-s` or
  `--saxon-jar` parameter instead of the base directory for Saxon-HE. This
  allows newer versions of Saxon-HE to be used.