Nope, Firefox still uses its own rendering engine and JavaScript engine—except on iOS, where it's essentially Safari with a UI wrapper. But that’s due to Apple’s ToS, not Firefox’s fault.
I assume the previous comment was about market share. It’s low, yes, but I still think Firefox has influence despite that. Having a third rendering engine is valuable—especially now, after Microsoft killed IE/Edge and turned it into a Chromium fork. The percentage might not be high, but the people who use Firefox are usually the ones pushing for keeping the web an open standard.
I assume the previous comment was about market share. It’s low, yes, but I still think Firefox has influence despite that. Having a third rendering engine is valuable—especially now, after Microsoft killed IE/Edge and turned it into a Chromium fork. The percentage might not be high, but the people who use Firefox are usually the ones pushing for keeping the web an open standard.