Simon Judd

What is your base resource set to? Also does the project you are editing have it's own PLAYPAL? I can't reproduce this issue myself.

What version of wxWidgets is it built with? Should say in the console log. I think there might be some issue with the version of wx that the flatpak SLADE...

Hmm, I think the best way around this would be to make revert undo-able via ctrl+z, and/or add a warning dialog when it's clicked

Ok so apparently the option has been there since 2015 (90b0b296) and defaults to true, so I guess at some point you must have turned it off  If you...

There is also libarchive, which I've managed to get working somewhat in the past. The main problem with it is I'm not sure it has any way to simply copy...

Does it only happen with your particular wad/zscript code? If so there might be something in it SLADE's zscript parser doesn't like

Looks like it can't initialize OpenGL on your system, make sure your video drivers are up to date