While we wait on an answer/fix for that, you can add the fonts to your page head or to all page headers using the properties of the page. To add it to a specific page just right click over the page name in the Pages list and choose properties, then choose the tab for Head and add the code you would usually add to the head of an HTML page. To add it to all pages go to the top of BSS and choose the little arrow next to the Export word on the Export button and the click the Export Options popup to open the Export settings. The tabs at the top will allow you to add things to "all" pages so if you add something in the Head Content section, that will be on all pages, same for Meta tags. Hope that helps for now. :)
Hello! Yes, I'm aware of the workaround that you describe.
I has a drawback though: The preview inside bootstrap studio doesn't reflect the changes from fonts inserted in this manner.
In any case, I think that this is something that can be easily fixed in the next version, so long as someone alerted the developers about it, so that's what I did :)