I only managed to figure out last night how to get Firefox to open multiple tabs on startup, each with a different page loading. And guess what? It was very simple to do.
Simple set your tabs up as you want at startup, and go to options and click ‘set as home page(s)’ It’s that little ‘s’ in parenthesis that’s important. Next time you start Firefox up, all the pages load.
Mine now starts with:
One issue with this is that everytime you hit the home page button on the browser toolbar, all four pages start loading in new tabs, meaning that you can end up with rather a lot of them!