Surprised nobody already suggested some kind of mouse gestures extension. I use foxy gestures and once you learn a few gestures (starting with closing a tab and undoing it) it becomes hard to live without it! Gesturefy is also a popular alternative.
Firefox
A community for discussion about Mozilla Firefox.
Genuine question: How are gestures faster / more efficient than clicking a button, or using keyboard hotkeys? Or is this mainly for notebooks, tablets and smartphones?
Compared to clicking a button I would say a lot faster as you don't have to move your mouse to start initiating your gestures. It's maybe more marginal compared to a short key. Still your hand is already on the mouse ready to execute a gesture. Personally I find it really convenient and for me it's the second most useful add-on after ublock. When using a browser on other computers that don't have these I find it really tedious and I am shocked at how much ad there is.
Thanks for the explanation, I might have to give it a shot.
Behind the Overlay.
https://addons.mozilla.org/en-US/firefox/addon/swift-selection-search/
"Swiftly access your search engines in a popup panel when you select text in a webpage."
I don't want to say its name, cause I worry (maybe unnecessarily) about making it a target, but there's a downloader for YouTube that's the only extension I've ever paid for.
Tab Center Reborn (and some css to hide the top tab bar) for sidebar tabs.
How it compares ro TreeStyleTabs?