Ah, right. TBH I mostly just don't do that, but I did throw together a script that takes a URL and just puts it on the clipboard and uses notify-send to tell you about it, so I can just paste into whichever window I want (and then tell the system that that script is my preferred "browser" to open http(s) URLs). This obviously adds a little friction, but it makes it trivial to open links in any browser/profile/window/tab-group I want.