Staudey can't reproduce this on my Plasma VM
Thanks for checking that. That's what I had hoped the answer would be. That means there's probably something I can do that will fix it. I just need to figure out what that might be.
I can understand why, when I click the menu's Hibernate command, after it wakes up the next time the menu is still present. That could just be a race condition that favors the hibernate command. But it also happens at times that have nothing to do with hibernating. That would tend to discredit the race condition theory. It happened just now, in fact, when I opened the menu and then returned back here to the Vivaldi window.
It looks like I have another mystery to solve.