I noticed that when it comes to addons, unregister() gets called both when disabling the addon AND when exiting blender.
I have an operation I only want to perform if the addon is disabled from the user Preferences, but NOT every single time blender closes.
Does anyone know of a way to differentiate between the two situations?
Some context: my addon needs to copy custom matcap files to blender's user path (datafiles/studiolights). The problem is deleting them only when the addon gets unchecked in the preferences, but not every time blender exits. Copying those files into that user path seems to be the only way to install a matcap.