Well I did not know that. Perhaps that's why it works so seamlessly. Well one of the upsides then is that switching to Firefox in IOS is very painless then.
My understanding was that until next year when EU+UK legislation regulating digital marketplaces comes further into force, all of these iOS apps for browsers like Chrome, Firefox, etc. MUST be wrappers around the exact same Webkit rendering engine that Safari uses. I think it’s cool that everyone can enjoy the better UIs today (myself included), but everything other than the UI is placebo.