🚀 [Story performance] Remove FOUT on font loading of amp-story-education #37928
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gmajoulet
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Amp-story-education installs 40kB of Open Sans fonts (3 weights) that load after amp-story-education so the critical path to install the fonts takes a significant time. Currently we don't specify any loading strategy which makes a FOUT (flash of unstyled text) that is registered as a CLS.
We can use https://www.industrialempathy.com/perfect-ish-font-fallback/?font=Open%20Sans to remove the FOUT by setting the fallback height of Arial to match the height of the font.