If I select from the menu Tools > Effects and filters > Video Effects and click on the Image adjust box VLC immediately terminates if I am watching a movie or it does not start if I make this selection prior to attempting to play a movie. Alternatively, I have attempted to change the gamma value via preferences, Tools > Preferences > Filters > Image adjust also without success as well as the ~/.config/vlc/vlcrc with the same result.
I am attempting to change the gamma value and from existing threads it suggests that hardware acceleration be disabled. There are 2 controls for hardware acceleration that I can find: Video > Output modules > OpenGL and Input/Codecs > Video codecs > FFmpeg. Disabling them makes no difference at all.
This is a new install with only one app installed, krfb.
My system information:
Operating System: Kubuntu 20.10
KDE Plasma Version: 5.19.5
KDE Frameworks Version: 5.74.0
Qt Version: 5.14.2
Kernel Version: 5.8.0-41-generic
OS Type: 64-bit
Processors: 16 × AMD Ryzen 7 5800X 8-Core Processor
Memory: 15.6 GiB of RAM
Graphics Processor: GeForce GTX 1080/PCIe/SSE
Following is the debug level log from attempting the first method above (use sliders).
https://pastebin.com/eXDqbxgN