I’ve been having the same problem for a few months now. Like others in the thread, I too have a Citrix Workspace session running at all times. Going off of the clipboard theory, I have discovered if I copy simple text to the clipboard in the Citrix virtual machine and then launch Brave on the physical machine, the problem does not occur.
So it does seem likely that there is a connection to the type of content in the clipboard. Presumably it is rich content types that produce the problem. If you are having this problem, try replacing your clipboard content with simple text and see if the browser becomes more cooperative.
As an aside, I also experience the problem in Edge, suggesting that the problem may be with the Chromium codebase that underpins both browsers.