Describe the issue
The Google Fonts CDN doesn't serve all characters available in some fonts. This is especially noticeable with fonts that support the box drawing unicode range, U+2500-257F (for example, Fira Code), while trying to use the Box Drawing Light Arc characters, U+256D-2570.

To Reproduce
Produce the CSS and HTML such that they render box drawing characters (best done with <pre> and a monospace font) and use a font from the Google fonts CDN that supports those characters (such as Fira Code). Note the results.

Clone the above HTML/CSS and adjust it to instead use one of the font files (by either hosting the file yourself or encoding as a data URI and using that) available in the downloadable zip files for the font. Note the results.

Note the differences between the two examples.

Expected behavior
The CDN should be serving CSS and font files that contain all characters available in original font files.