Change Thunderbird, Firefox Language Settings

Just after I installed Debian, I immediately felt the need to install Firefox and Thunderbird, as they are my favorite web and mail browsers. As they are not present in the debian repositories, I had to use the ones from linuxmint (I added to my/etc/apt/sources.list): deb http://debian.linuxmint.com/latest testing main contrib non-free And after I installed Firefox and Thunderbird, I found myself with a Firefox in Afrikaans and Thunderbird in Arabic. Why this weird combination? It…

"Change Thunderbird, Firefox Language Settings"