I'm not the person you asked, but I could have written the exact same comment. For me, SSB and chromium's much better profile functionality are the biggest hurd

I'm not the person you asked, but I could have written the exact same comment. For me, SSB and chromium's much better profile functionality are the biggest hurdles when trying to move to Firefox or a Firefox-based browser. I also encounter way too many bugs and weird behaviours in Firefox web dev tools. I hate chromium dev tools too, but I find it a more consistent bad experience. The closest I've been to fully switching has been Zen browser. The ability to completely hide the browser's UI so you only see it when hovering is almost good enough to forget all other issues I got with Firefox. That "focus mode", vertical tabs, and side-panels, are the best UI elements to come to browsers since tabs, and I hope and expect all browsers copy them soon enough.