I had a quick look (because actually, having tabs load for a specific project would be quite helpful) and it looks like that might offer some of what you want?

I had a quick look (because actually, having tabs load for a specific project would be quite helpful) and it looks like that might offer some of what you want? https://addons.mozilla.org/en-US/firefox/addon/simple-tab-groups/ https://addons.mozilla.org/en-US/firefox/addon/simple-tab-gr... https://github.com/drive4ik/simple-tab-groups https://github.com/drive4ik/simple-tab-groups