A visual explorer for all of the GUI styles in game. Default keybind is Ctrl + Shift + S
Lua libraries for use by other mods and submods that are parts of a larger mod.
When the Style Explorer window is open and pinned, the close button doesn't do anything and when you have another window opened the Style Explorer's close button will close the other window that is open.
I haven't been able to reproduce this on my end at all. Do you have any other mods enabled?