Firefox default browser in Linux

How to set Firefox as default browser for Thunderbird and other applications in Debian or Ubuntu Linux?


System wide default
Define Firefox as system wide default web browser by running:
update-alternatives --config x-www-browser


KDE4 default
To use Firefox as default in the KDE4, you must open:
Desktop Settings / Personalised Settings -> Default Applications -> Web Browser ->

or in latest KDE open:
System Settings / Default Applications -> Web Browser ->

check: 'in the following browser'
set value: /usr/bin/firefox


Thunderbird default
In Thunderbird open menu:
Edit / Preferences / Advanced / General / Config Editor

Change Filter to:
network.protocol-handler.app.

Add or modify existing preferences. Double click specific preference for modification or,
if preference is not in list, right click to empty area and choose: New -> String

Insert key name: network.protocol-handler.app.ftp
Value: /etc/alternatives/x-www-browser

Insert key name: network.protocol-handler.app.http
Value: /etc/alternatives/x-www-browser

Insert key name: network.protocol-handler.app.https
Value: /etc/alternatives/x-www-browser


Edit Thunderbird config directly
Optionaly you can edit your Thunderbird config directly.
Thunderbird preferences file: ~/.thunderbird/*.default/prefs.js


Note
If you have not selected your default browser, you can replace string /etc/alternatives/x-www-browser by /usr/bin/firefox (with appropriate path)

Keywords: thunderbird url open
Source: novell.com