This should be a pretty simple 1-line CSS fix, just default to standard system fonts if the "dg" font isn't available.

No, it’s loading the font in JS for some reason (rather than a regular @font-face) and going out of its way to break the page if that fails, rather than ignoring it as it should. `font-family: dg` is fine, it’ll fall back to the user’s default font (which will typically be serif).