Hi,

Where do you encounter this issue?

I was reading Mail using Hotmail, I needed to copy some questions and paste them in my reply, when I got the pop up message saying I had to use keyboard shortcuts.I see now that it happened when I try to copy and paste in the reply window but not in the original message,

Got it now, thank you for bringing that up! I've been able to reproduce and reported the issue on WebCompat.

Hello

Apparently, a similar question https://support.mozilla.org/en-US/questions/1548786

You can test, the preference, dom.event.contextmenu.enabled value false

1 - Go to configuration editor https://support.mozilla.org/en-US/kb/about-config-editor-firefox 2 - Enter a search term dom.event.contextmenu.enabled