More info, starting vlc from the command line:
$ vlc "videoTest.mp4"
VLC media player 3.0.18-rc2 Vetinari (revision 3.0.13-8-g41878ff4f2)
[000055feb8f33580] main libvlc: Running vlc with the default interface. Use
'cvlc' to use vlc without interface.
[000055feb8fe4a90] main video output error: video output creation failed
[00007ff234c57d00] main decoder error: failed to create video output
[000055feb8fe4a90] main video output error: video output creation failed
[00007ff234c57d00] main decoder error: failed to create video output
[h264 @ 0x7ff234efad00] get_buffer() failed
[h264 @ 0x7ff234efad00] thread_get_buffer() failed
[h264 @ 0x7ff234efad00] decode_slice_header error
[h264 @ 0x7ff234efad00] no frame!
[h264 @ 0x7ff234d30bc0] get_buffer() failed
[h264 @ 0x7ff234d30bc0] thread_get_buffer() failed
[h264 @ 0x7ff234d30bc0] decode_slice_header error
[h264 @ 0x7ff234d30bc0] no frame!
QObject::~QObject: Timers cannot be stopped from another thread
