Font loading error: downloadable font: kern: Too large subtable, table discarded

Question

I am trying to use the "Open sans" font into my web page, and only in Firefox, I get this error in console:

downloadable font: kern: Too large subtable, table discarded

Here is the CSS:

@font-face {
    font-family: Open Sans;
    src: url(OpenSans-Semibold.ttf);
}

Answer 1

I did some digging around and the issue seems to be with Open Sans subset itself.

This user (https://stackoverflow.com/a/16041637/4799071) seemed to run into the issue when they downloaded the font from Google Fonts. Try downloading it from Font Squirrel and see if that fixes it.

Answer 2

This is a problem in Firefox, which cannot handle Open Sans font in its entirety. The bug still exists as of Firefox v 75.0.

They have marked the problem WONTFIX in 2015:

• https://bugzilla.mozilla.org/show_bug.cgi?id=1185685