Ubuntu – Alt-Gr key not working properly on Firefox

firefoxfirefox-extensionskeyboardlastpass

When using Firefox I have troubles with the use of Alt-Gr inside an open menu window (address bar, search bar, addon popup).

This is particularly annoying since, for instance, when using LastPass I cannot enter my email because the window gets closed as soon as I press Alt-Gr (I need it to type the @ sign).

I tried Safe Mode as well as previous Firefox versions, the problem doesn't fix.

The issue came out after updating some package (apt-get upgrade)
I'm using Ubuntu 16.04, (with a Spanish keyboard layout)

How can I fix it?

Best Answer

The solution should be, to activate the checkbox Prevent accessibility services from accessing your browser in Firefox settings under Privacy & Security -> Permissions