Thanks for the info. Update v0.12.3 was a potential fix for this issue, but I guess it doesn't work. I haven't been able to replicate on my headset, so I've been guessing at potential solutions. Looks like I need to find a different work around. There's something wrong with how Unreal Engines interacts with the Quest OS when getting the UI render size. In the meantime, you can try restarting your headset. This usually fixes the issue.
By the way, are you using any third party apps that can affect the Quest resolution?