I'm an Xfce user, in the habit of dragging windows around with the "super" key + left mouse button.
For instant access to the browser back button, I have it positioned in the far top-left corner so that just swiping the mouse in that direction hits it without having to look at it. Unless it's on the other monitor, which is mildly annoying when it happens but you know, probably not by enough to change my decades-old habit of buying the cheapest and simplest mouse that's easily available and looks like it might not fall apart in a week, much the same way as I tend to shop for socks: reluctantly, when it's necessary.