This is a meta issue for our Firefox support in Web (issue list) and this can be used to track the limitations and gaps we currently see today on Firefox.

Currently we have two major blockers: Full Keybindings Support and PWA.

• Keybindings. Firefox doesn't allow web applications to override some of its predefined keybindings by any means, no matter if it's a in full screen mode. It means basic keyboard shortcuts like Ctrl/Cmd+N to create new file, Ctrl/Cmd+W to close current file don't work. The experience can be improved only when one of followings upstream issues are resolved
  • Override keyboard shortcuts in full screen. bugzilla
  • keyboard.lock bugzilla
  • PWA support Usually in PWA desktop mode, you can have full keybinding support bugzilla
• PWA. Only with this, users can save Web to desktop or taskbar for quick access, and potentially full keybindings support

Besides, we have some nice-to-haves:

1. Clipboard read support. Currently web applications are only allowed to read clipboard in user-initiated event callbacks. It means we can't have customized keybindings or context menu entries for Paste command. Clipboard Service API not supported in FF #84084
2. Unicode support for regex. We adopted Unicode mode in language definitions, find/search, etc already but Firefox is lacking support for it. bugzilla, [Firefox] Firefox errors on the markdown's unicode regular expression for word definitions  #83698