@carlwgeorge thanks for the report, however none of the stack traces in your paste contain anything related to mkvtoolnix. Also, mkvtoolnix can't possibly be able to crash gnome-shell directly. I think it just exposed a bug in either gnome-shell or one of the drivers. Please report the crash via abrt (System Tools -> Problem Reporting) if possible. Does it happen only under Wayland or under Xorg as well? Does it happen with any other desktop environment?
wfica.sh crashes in the same way as if I take libidn from f28.
This doesn't seem to work for me:
$ /usr/bin/mkvmerge --output /home/username/Videos/VTS_01_1.mkv --language 0:und --language 1:und '(' /run/media/username/NLATP/VIDEO_TS/VTS_01_1.VOB /run/media/username/NLATP/VIDEO_TS/VTS_01_2.VOB /run/media/username/NLATP/VIDEO_TS/VTS_01_3.VOB ')' --track-order 0:0,0:1 mkvmerge v28.2.0 ('The Awakening') 64-bit '/run/media/username/NLATP/VIDEO_TS/VTS_01_1.VOB': Using the demultiplexer for the format 'MPEG program stream'. '/run/media/username/NLATP/VIDEO_TS/VTS_01_1.VOB': Processing the following files as well: "VTS_01_2.VOB", "VTS_01_3.VOB" Warning: '/run/media/username/NLATP/VIDEO_TS/VTS_01_1.VOB': A track with the ID 0 was requested but not found in the file. The corresponding option will be ignored. Warning: '/run/media/username/NLATP/VIDEO_TS/VTS_01_1.VOB': A track with the ID 1 was requested but not found in the file. The corresponding option will be ignored.