@dzoniis not sure if it would be enough to break it, but I believe the format should be “truetype” and not “ttf”. Also, double checking: I’m assuming you ran yarn build before testing?
Yep, they are in dist/fonts and location of Barlow-Regular.ttf is in that location
I have no 404 errors or something like that, it just won’t display it
If so, that will confirm that the browser a) is picking up your style and applying it to the element you’r testing with and b) knows it can’t find the Barlow font.