[BUG] Tabs "forgets" set `--headerheight` when switching workspaces

[firinael]

Pretty simple and consistent behaviour:

Just use the "manage workspaces" command to switch to another workspace with the core plugin, and the --headerheight variable will be "unloaded" so to speak.

I've tried adding it as a constant to my theme but that wasn't enough.

[Signynt]

I've got the same issue using it on iPad. Causing the plugin to refresh in any way fixes the issue (such as changing one of the settings, or turning it off and on again), but it's still annoying since I frequently switch between workspaces.