Right side chat/compendium box broken, can't expand

For some reason, the box to the right that has stuff like the chat box, player journals, etc… cannot be expanded and is permanently shrinked. Is there a fix to this? I’m not sure how this happened or if there’s a way to replicate it. It simply happened overnight without me or anyone doing anything.

That sounds like a module is probably misbehaving and causing that. Did you update your modules recently? If you did, try to downgrade any module you use that you think might cause this behavior. If you didn’t update your modules… maybe do try to update them?
If you’re stuck, you can always enable Safe Configuration (which will disable all modules and deactivate the scene and stop playlists), then you can re-enable your modules in smaller batches until you find the one causing the problem.
You can see how to enable safe configuration here : How to enable Safe Configuration - Docs - The Forge