The thing is, as a solo developer, you just have to be ruthless with cost/benefit. Either I give the same experience to maybe 2% of the users, or an overall improvement to 98%. Is it ideal? No. But a lot of things are about tradeoffs and deciding where you spend your resources.
Ok, people here don't like it. They can make their own tradeoffs. But in my opinion my choice is not that crazy.
Still doesn't change my assessment it's not worth it.
Edit: especially since according to experience, when Firefox doesn't work for users, they just switch to another browser.