Firefox only: Google's recent improvements to Gmail's labels broke one of Better Gmail 2's most-loved features: Folders4Gmail. Folders4Gmail displays labels with slashes in them as subfolders of a parent label, and I must say, I've missed it a whole lot this week.
Luckily, rockstar userscripter Arend v. Reinersdorff updated Folders4Gmail to work with Gmail's new drag-and-drop, hide-and-show label mechanism, and I just posted his new version in the extension. Grab the newest version 0.8.3 of Better Gmail 2 to get back Folders4Gmail functionality as well as Hide Spam Count. Check out what Folders4Gmail looks like in action in the screenshot. Arend recommends showing all your labels to get full-on subfolder action with Folders4Gmail enabled.
Also, thanks to the product manager at Google Apps who contacted me and Arend personally, apologised for making the label changes without sooner notice, and offered support and encouragement for updating the script and add-on. That was a nice big pat on the back for something a lot of developers have put time into. (Thanks also to the users who contacted Google asking them for their subfolders back!)
Until Mozilla Add-ons approves the newest version of Better Gmail 2, check off "Let me install this experimental add-on" next to version 0.8.3 at Mozilla Add-ons.
Better Gmail 2 [Mozilla Add-ons]
Better Gmail 2 Updated for Gmail's Label Enhancements [Smarterware]