File "c:\Users\username\Desktop\blender-3.0.1-windows-x64\3.0\scripts\addons\greasepencil_tools\timeline_scrub.py", line 785, in register_keymaps
km = addon.keymaps.new(name="Grease Pencil",
AttributeError: 'NoneType' object has no attribute 'keymaps'