I really wanted to like it, hoped it would do everything I wanted, it even looked like it did! Alas it wasnt meant to be! Back to Chrome for me.
Quantum is fast, its smooth, it uses a crapload less memory. It has some fantastic plugins. And some not so fantastic ones. Namely no matter what I do I cant get it to keep my lastpass logged in. Lastpass forums say delete this, do that, and so on, firefox forums dont say anything about it other than disable all your plugins and see. Well 2 reloads later and it still asks me to authenticate every time I open firefox. There were a couple of other plugins not quite working the way I expected compared to their Chrome counterparts.
Next issue I had was with my displayfusion move to next screen button being lost as soon as I had 3-4 tabs open. I did find a work around by customizing the menus and adding in a blank space at the end of the tabs menu. This then stopped the new tab button from being next to the last tab and placed it at the end all the time. I reset that and found another workaround for it in displayfusion itself, I managed to move the button to the right a little and that fixed it. Mostly.
Really the main issue for me was the lastpass thing. Im not disabling 2FA just for firefox, and theres not really support from lastpass other than delete, reinstall.
Maybe in the future it will improve to the point of me liking it again like the old days. For now Chrome will continue to reign supreme on my devices.