Is there a add on or a feature within firefox that allows you to choose what tabs you want at start up. For example i know you can set multiple homepages at start up. But can you choose what tabs to open at start up. For example: I open Firefox I get the start up google page. Can i choose what session i want? e.g a box that opens up all of my bookmarked gaming tabs. a box that opens up all my social networking tabs etc.

Please respond as this feature would be very useful.