Library Override can't edit this properties from an override data-block

Ok. So I have a rig with a python UI addon, and I want to link the rig to a scene. I’m using Blender 3.0 beta in where there’s no longer an option to make proxies, only library overrides. And so, I use library override.

But when I want to edit the rig using the python UI addon, I can’t, and I get this error saying that you can’t edit this property from an override data block.

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I found that I can make everything local, and the addon works. But I don’t want to do that. Is there a way to make the python UI addon work without making everything local? (Also, I’ve tried to just make the armature local. But when I save and reload the file, the rig breaks)