@hideki Just leaving them open is easier than manually adding them to bookmarks. I can type on the search bar and if the tab is open it will take me straight there. Plus, if I find later that I don't need it anymore, I can just close it and won't have another page cluttering my bookmarks.
The only bad thing is when I accidentally close the window and lose it all, but there are ways to restore it and I have a backup.
there's important stuff here that I'll get to (someday)