You can run the following and try it for yourself. Don't forget to highlight some text before right-clicking an image (e.g. https://en.wikipedia.org/wiki/The_World_Factbook)
TMPPROF="$(mktemp -d /tmp/ff-tmp.XXXXXX)"
/Applications/Firefox.app/Contents/MacOS/firefox -no-remote -profile "$TMPPROF"Also a few of the menu items are new since the latest ESR (the AI stuff in particular), so you won't see them if you are running v140.