Why are there many hundred Chromium based browsers, but seemingly very few Firefox based browsers?

https://thelemmy.club/post/718914

Why are there many hundred Chromium based browsers, but seemingly very few Firefox based browsers? - The Lemmy Club

Your searching on this may be skewed due to Firefox not being the equivalent of Chromium. Firefox is not actually the browser engine. Firefox is based on the browser engine called Gecko. There are actually a number of other Gecko based browsers they just aren’t very popular or are for niche use-cases.

en.wikipedia.org/wiki/Gecko_(software)

Gecko (software) - Wikipedia

Isn’t Safari Gecko-based? Safari has a huge market share.
Safari is webkit based. Which was also the basis for chromium, but it has diverted a lot from it. Other webkit based browsers are gnome web, KDE konqueror.