I'm using Ubuntu with Gnome shell customized to look like the old Gnome pre 2014, or was that 2012? I have a virtual desktop per customer and one Firefox window per desktop. One "customer" it's my own pet project of the moment and another one is where I keep my email, WhatsApp web and Telegram desktop and other social media in their own private container tab. So I group per window and I need less functionality from the browser because I rely more on the OS.
I believe that Gnome calls those desktops Activities but I disabled nearly all of the Activities related stuff. I have hotkeys to move to desktops and I use them like old school virtual desktops, a fixed number of them. IMHO yhe less the screen moves the better it is.