If you do not like the behaviour of Firfox’s new url bar you might want to take a look at the oldbar addon and set browser.urlbar.matchOnlyTyped to true.
The webmail frontend of Scalix only supports certain browser types which it checks using the User Agent string supplied by the client. Due to debians move to iceweasel this fails.
With the help of a plugin called User Agent Switcher you can use these settings to make things work.
And again an upgrade changed the UI. Each tab has its own close button, the one on the far right, closing the active tab is gone. If you like me liked the old behaviour better go to about:config and change browser.tabs.closeButtons to 3.
For more helpfull hints go to lifehacker.com
Update: It seems like there will be more options I’ll tweak, for example set network.dns.disableIPv6 to false, network.protocol-handler.external.mailto to true and network.protocol-handler.app.mailto to icedove
Since I work with Firefox on Windows and Linux I always found myself looking for the preferences in the wrong place. Luckily there is a plugin called Preferences Mover:
Move preferences menus on Linux to where they belong on Windows (or vice versa).