Add dark mode to linux

[midvightmirage]

Editor

Resource editor, Map editor

Description of your feature request

Now that windows has had dark mode for a while, how about we get it. Light mode hurts my eyes and with reduced brightness I can't see anything on my screen.

Mock-up

[sirjuddington]

SLADE on linux has always supported dark themes, you just need to set your DE theme to a dark one.

[mangomeep]

You can add something like GTK_THEME=Adwaita:dark to your .bashrc or equivalent shell configuration.