I've been on Chrome for a long time, tried to switch to FF when Quantum came out and couldn't hear myself think over the sound of my laptop winding up.
Once you realize that not being evil isn't a priority at Google anymore this explanation actually makes some sense.
Then I tried it in Chrome and found that Gmail behaves like shit in Chrome too.
The solution however was to drop Gmail's web interface. Switched to a desktop client. If you're on MacOS I think MailMate is the best.
Couldn't be happier. And this advice is independent of your browser choice.
PS: the fact that Google's online properties are optimized for Chrome should make you realize that Chrome is the new IExplorer and it's our fault for allowing it to happen ;-)