Hi, Opening links from thunderbird stopped working. I have tried in safe mode, network.protocol-handler.external-default is set to true, network.protocol-handler.app.http and network.protocol-handler.app.https are set to the full path of firefox ( /usr/bin/firefox-esr) with no success. #ps ux |grep thunderbird ps ux |grep thunder alain 20137 0.0 0.4 275480 37824 pts/4 R+ 07:45 0:00 [thunderbird] alain 20152 0.0 0.2 373876 22520 pts/4 R+ 07:45 0:00 /usr/lib/thunderbird/thunderbird https://www.lairdubois.fr/creations/4449-signaletique-wc.html alain 20154 0.0 0.0 13704 2224 pts/6 S+ 07:45 0:00 grep --color=auto thunder alain 21383 7.8 3.1 1775784 258748 pts/4 Sl+ 07:35 0:46 /usr/lib/thunderbird/thunderbird -safe-mode so it seems that thunderbird tries to open the link by itself instead of requesting firefox to do so. What should I do ? (Debian Jessie Thunderbird 45.8.0)