What happens when you try to detach a tab? For example, it simply stays on the bar, it moves left-right, it adds a bookmark, etc.

I assume the long way still works: right-click the tab > Move Tab > Move to New Window

It doesn't move at all. It's like the tabs are no longer responsive, except the right click menu still works (your alternative suggestion of moving to new window works).

For what it's worth, my computer went to sleep, and when it woke the functionality was working again. I don't consider this solved, but I'm no longer able to provide any live logs/diagnostics.

That is odd because if there was some glitch before sleep, why would sleep help?! Hmm...