I literally searched for >30min trying to find this extension (and hoping it existed) on FireFox because I loved it so much on Chrome. Sure I ended up wading through more than 100 other extensions before I saw it hidden away on page gazillion, but literally no one has such as simple UI that just does what it needs to do. I've never spent this much energy tracking down an extension before. Full functionality, ZERO clutter, 10/10.