Youtube Noglafy by Ty-gone

Nogla appears on every YouTube thumbnail. He shows up in the bottom corners or bottom-middle, sometimes flipped, always pointing into the thumbnail. Comes with three Nogla cutouts built in, and you can upload your own PNG/JPG/WebP images through the popup - tag them as "points left", "points right", or "neutral" and they'll place themselves intelligently.
Optional jumpscare mode (off by default): on watch pages, there's a small chance every 10–20 seconds that Nogla fills the screen with a boom sound effect. Once per video max. Tweak the odds, interval, and volume in the popup.
Works on Chrome, Edge, Brave, Opera, and Firefox.