I don’t think Gecko is a requirement for the addons. The Orion Browser supports (many but not all) Firefox’s addons and its webkit. So it is feasible although probably hard to obtain a 100% compatibility. I still use Firefox on Ios because I prefer the UI but not all sites works well with it. Also the ios team at Mozilla is very small allegedly based on some public threads on the internet.
I don’t think Gecko is a requirement for the addons. The Orion Browser supports (many but not all) Firefox’s addons and its webkit. So it is feasible although probably hard to obtain a 100% compatibility. I still use Firefox on Ios because I prefer the UI but not all sites works well with it. Also the ios team at Mozilla is very small allegedly based on some public threads on the internet.