Until support for it landed, it had never dawned on me how handy Growl notifications could be in a web browser. Now, I can’t imagine life without them. If you have Growl installed on your Mac (and if you don’t, you should!), Firefox 3 makes great use of it.
If you’re not familiar with Growl, it’s a notification system that applications can use to unobtrusively present notices to the user. They appear as small bubbles or boxes (the appearance of which is very highly configurable) that fade away after a few moments. You can also configure Growl so that the notifications are sent to other Growl-equipped computers at your home, and to only fade out if you’ve touched the keyboard or mouse recently.
Firefox takes advantage of this if you have it. When downloads complete, a Growl notification is issued. If you have add-ons that need updating, Growl lets you know. If there’s a Firefox update ready to install, Firefox uses Growl for that too.
Growl is as close as Mac OS X currently comes to having a standard system for these types of notifications, and it’s a real pleasure to see Firefox taking full advantage of it.
Extensions can even easily use Growl too, by using the nsIAlertsService interface, which previously only worked on Windows. I hope to see lots of extensions take advantage of this soon!