Does anyone else find Firefox hard to develop for?

I know that there has been a recent push in many privacy conscious circles to move from Chrome to firefox. I haven't been able to move from Chrome myself due to work and some personal extensions ive created that I don't want to re-write/re-configure.

Also, I think the dev-tools are comparable between chrome and ff.

Anyways, I've been working on some web-apps recently that are going to be firefox supported, but I just find there are so many things on caniuse.com where there is only partial support for firefox. Things from flexbox to range inputs are mostly working 'except for a few bugs' which often impact my work and are annoying/impossible to work around?

I just find way more stuff in firefox that renders differently compared to any other major browser.