Personally, I keep generally 1 window per topic and multiple tabs in that window. They're kind of like medium-term bookmarks. For example, I'm shopping for a carseat, looking for a replacement for my front gate, working on a React project, a RaspberryPi project, and playing with Vagrant and Ansible for something else. I start something, but have to set it aside because of something is blocking me (I need to solder stuff together for rPi, verify my kid's hight/weight for the baby seat, talk to the wife about the gate, or I just get in the mood for switching projects).

After I finish a project (or abandon it) I can lose all of the tabs.

Unfortunately, this can end in 100s of tabs open at a time.

At work it's very similar. Especially, because a lot of things are interrupt driven and I'm jumping between short, medium, and long term projects.