The applications you mention; Opera, Vivaldi doesn’t have native tabs like the other two applications you mention; Safari and Finder. Unless I am mistaken. I recently downloaded Vivaldi and I don’t see the ability to use macOS native tabs with the look and feel of those in Finder and Safari (the colored tabs can be turned off but they do not revert to being a pimped-up Safari browser because of that. Opera; the same - except for the colored tabs.
I would suggest sticking to the native tab suggestion and not leaning up against any other application for the Mac that doesn’t per default use the macOS native tab look, feel and function.
I personally turn off the Tab-part of TotalFinder whenever I use said app. I dislike the lag that is on creating and closing out of tabs which I previously asked to be sped up(via a different older username on these boards). I think it has to do with the nature of adding a non-native Tab system to the Finder in Real Time adds to some lag because of the patching involved. That’s as far as I got in my reasoning. My Mac is no slouch and performs well.
I wanted to give my opinion on the matter and I hope I’m not considered a troll because of my <2 post count and wording in this reply.