Hi Clifton,
I’ve been having this kind of issue myself from time to time. The last-known layout state of Editor windows and tabs is not stored per-project, so deleting Intermediate and Saved folders does not help indeed. I believe this information is stored system-wide for your OS user, affecting different projects and even engine versions.
In any case, when this kind of problem happens, the easiest way I found to work around it is to make your window/tab get keyboard focus (in your case, by clicking the Window menu and the User Parameters item), then using the Windows key combined with the up/left/right arrow key. This should bring the window back to view from wherever it was.
Let me know if that helps!
Best regards,
Vitor