"Ok, I hope I have enough to type here. I recently did a fresh install of Linux Mint 20.1 I wanted to do mainly flatpack versions of software I use. FF works great, I uninstalled the FF that came with my LM 20.1 preinstalled, but for two things. Video not from YouTube, like from Instagram or Facebook for example, were glitchy/clippy. A few extensions from FireFox would not fully work or work at all. I could not install the COAPP for Video Download Helper. So for gigles, I REINSTALLED the original FF from the Software Manger NON-FLATPACK. EVERYTHING works great now, kinda disappointed. If any one has an idea on why this was happening, please if possible, do tell."