very nice. been looking at the "system-ui" font saying "damn that looks great I must try it", then as I continued to browse further down got confused. Why does every font look the same? It must be my design-ignorant brain not picking up on the subtle differences in these fonts? They're clearly brilliant though.

as I couldn't spot any differences in any of them (and all of them looking fantastic and really similar or same as the rest of my system) ...

Then it hit me, so went to

  Firefox -> 
     settings -> 
        Fonts -> 
           Advanced -> 
             "Allow pages to choose their own fonts, instead of your selections above"

problem solved :) I was no longer staring at "DejaVu Sans" in every box.