Another couple of cool Firefox features which most people probably already know about.
How many times have you closed a tab only to realise “Damn…I still wanted that open!“? Well I do that about everyday and although you have the general history manager…if you’ve visited 100 sites that day it’s a pain to wade through to find the tab you just closed.
Instead you can visit the History menu and see the item “Recently Closed Tabs” for a list of the last 10 viewed tabs. From memory there is also an addon which allows you to “undo” a close operation on a tab, but this menu option is cool!
Another thing is making sure you get alerted whenever there is a JavaScript error, I think this is quite important as a developer and although you do have the “console” it’s nice to have an “in your face” reminder that there is an error on your page.
To turn this on using the invaluable Web Developer Toolbar addon, click Tools -> Web Developer -> Options -> Options and under “Miscellaneous” you can choose up to 3 options for opening the console (you can also get to this from Options -> Options on the actual Web Developer Toolbar):
- When there is a CSS error
- When there is a JavaScript warning
- When there is a JavaScript error
It’s this last option that I turn on during development to get an error popup. Note that it is sometimes best to turn this off when surfing the web as there are SO many sites which have little JavaScript errors, causing popup hell 
Actually the UNDO for closing tabs is built in without any addons, just right click on the tab bar and click UNDO
Raul Riera
February 18th, 2008
Ah nice one, I never knew that was there! That’s a much nicer way to do it. Thanks Raul
Michael Sharman
February 18th, 2008
I didn’t know about the recently closed tabs history. That is awesome.
Ben Nadel
February 19th, 2008
That is pretty cool.
I recently learned about using multiple profiles via “firefox.exe -profilemanager” from the command line. (it only works if all Firefox instances are closed.) But that’s not the cool part…
You can open two separate Firefox profiles at the same time using “firefox.exe -P profilename -no-remote” for as many profiles as you have created. This means mulitple separate google accounts logged in and open at the same time in separate browsers, etc. Very handy! Separate add-ons, separate themes, etc.
I believe you can also set the path of the profile and make it a network location enabling you to use the same profile from anywhere on the network.
Windows and Linux alike. Make shortcut icons for each profile and life is grand!
Garrett Williams
February 19th, 2008
Separate profiles? That’s cool, I’ll have to check that out.
One ‘lightweight’ profile for normal surfing and one plugin heavy one for development.
I like it!
Thanks Garrett
Michael Sharman
February 19th, 2008