Several projects underway at once, each in its own virtual desktop. Each desktop might have two or three browser windows open, each with several tabs.

As I tire of one project I switch desktop to another that's more aligned to my frame of mind.

I don't tend to kill old browser windows because they serve as a refresher to remind me where I'd got to with a certain problem, or a particular research issue. Only when I've reached some sort of resolution do I kill tabs or even whole browser windows.

Those tabs sure mount up.

Occasionally I try a different workflow but I gravitate to this habit. It seems to work for me.