Bit late to reply, but seems ^A and ^E (jumping line begin and end) at least do work in Firefox. But for example ^T (letter transpose) do not work on macOS Fir

Bit late to reply, but seems ^A and ^E (jumping line begin and end) at least do work in Firefox. But for example ^T (letter transpose) do not work on macOS Firefox, which I'm quite accustomed to use also. But ^T works fine same macOS Safari and Chromium. Firefox apparently has its own input method which do not implement all what macOS supports.