That tabs overview only shows the tabs in the current window, which is not what he or I am looking for. I followed your link to the extensions, which was helpful, but the listings were all so sketchy, with no screenshots of what each one looks like, nor a single user review. So I installed the first one, which is supposed to show me a list of all open tabs... Well, when I clicked on it, it CLOSED EVERY WINDOW & TAB, and put them on one list!! So now, I have no clue as to how to reconstruct & reopen the windows I had open, nor is there any real directions as to how to do it!
Each sub-group says: "save this window", "open links in tabs" & "remove" with no explanation as to what any of that means. Save this window? Save it to where, I want to reopen it, not save it. Open links in tabs, huh? Will that open every tab, or link, as a tab, or? So now I can see all the tabs, but it completely messed up my current layout, closing everything, including what I was in the middle of watching... Why doesn't Safari show more information about each extension, so this kind of mess doesn't happen?