Hello. I am using the Gnome Edition.
The latest version of Brave, specificaly Version 1.8.85 Chromium: 81.0.4044.122 (Official Build) unknown (64-bit), has a bug in Picture-In-Picture, where when enabled results in a white window that is unresponsive. The audio keeps playing, and the browser is still usable. I tested Firefox and Chromium and they dont have an issue.
Here is a GIF with the issue: