However, you can never guarantee the font text will be rendered in, so if you precalculate you may damage things. Web fonts may fail to load for a variety of re

However, you can never guarantee the font text will be rendered in, so if you precalculate you may damage things. Web fonts may fail to load for a variety of reasons. Some users will force their own chosen fonts. In Firefox: Setting → Fonts → Advanced → untick Allow pages to choose their own fonts, instead of your selections above. I’ve done that for the last four years, as it makes the web so much better.