kernest.com seems to regularly run a little slow, which slows down page rendering, so this would be a way to avoid that problem.
I got close on this, but ran into a problem with getting the actual font files from Kernest servers. They return HTTP 417 error, and I'm not sure why. I'm attaching a patch of my progress. I'll come back to this later if no one else picks it up.
Updated patch applies against current 6.x-2.x-dev. I'm now getting 502 proxy error responses back when I try to load fonts. I get the same error when I try to load the fonts directly in my browser, but not when they're loaded on an actual page. I tried copying every HTTP header my browser reports sending with a successful request, but it still fails.
I contacted KERNEST to ask if they have any ideas.
@sreynen, Thank you for working on this, I wish I were a coder and could help you. I'll just give you my moral support and thanks.
I heard back from KERNEST. They don't really support downloading the files if you're not logged in to their site. The module can't log in to KERNEST, so any solution to this would rely on working around KERNEST's system, which I'd rather not do.
Meanwhile, I think #930066: Make it possible to include local installed fonts (local on the webserver) makes this largely irrelevant, since it allows you to server fonts locally (from KERNEST or anywhere else). That requires a manual download-upload from KERNEST, but as that's also what KERNEST is expecting people to do, I think it's okay.
So I'm marking this as "won't fix" for now. If KERNEST changes their API to allow this, I might try again. Until then, I suggest using the new local_fonts font provider to server KERNEST fonts locally.
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