User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.1) Gecko/2008070208 Firefox/3.0.1 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.1) Gecko/2008070208 Firefox/3.0.1 Having 30 tabs open on the browser, and trying to create a an easier space to work with, I was thinking that for the future of Firefox, you could incorporate Hierarchical Tabs, where we (the user) would be able to create a master tab which we would be be able to group a bunch of like tabs into one tab. When clicking on the "Master Tab", the Tab Bar would expand below it to reveal the grouping of tabs in the "Master Tab". Reproducible: Didn't try Steps to Reproduce: 1. 2. 3.