In Firefox 85 the Alt+Left arrow shortcut causes it to navigate back in browsing history. It does this even when a text field is focused and typed in which is just too much of a bad design for me, to put it mildly (it's more like Design to Error than Design for Error).
This happens in both Windows 10 and in Ubuntu 20.10 as far as I know. The only time it doesn't happen? In macOS, when the same shortcut is set on a system level to make the caret jump to the next word.
If I make a single mistake while using the arrow keys to navigate in any simple text field on the web, I lose everything I spent the last 10 minutes typing.
I want these shortcuts gone from Firefox. How is that accomplished?