Absolutely phenomenal. I had the thought "Huh, I wonder if someone made an extension to just watch youtube shorts as videos, because I hate the Youtube Shorts interface" and googled "firefox extension youtube shorts as videos" and thought there was a bug, because there was no way there was an extension literally called exactly what I searched. "Is this an AI generated link or something?" and then... no. Installed, it works exactly as described, and I couldn't be happier.