Comment by matser
Thanks! It has some cons, like worse scanability. But I think its really cool that you can have something open next to your paragraph, especially when you need to consult the popup quite often. Like, a table with a bunch of data would also be quite nice with this approach I feel.
If you have any feedback I'd love to hear it!
The way https://gwern.net/ does it is quite good.
The links open in a window, so you can still have centre aligned text with popups.