> tells you CLS bad mkaaaay... and guess what FOUC causes, layout shifts
I haven't had a problem here (with layout shift). As long as you specify width + height of images in the HTML, and you don't have dynamic content pushing the layout about as it loads it in your page header, you'll likely get a high CLS score as it has some leeway.
And sounds like `font-size-adjust` from the OP is helpful in avoiding layout shift when the stand-in font is swapped out for the custom font when it arrives? I haven't found this necessary though.
I'd argue that's not "avoiding" but "minimizing". As in, the average shift will be by fewer pixels. The shift is still there; the two fonts will practically never match in size perfectly, causing e.g. word wrap to happen differently.
I haven't had a problem here (with layout shift). As long as you specify width + height of images in the HTML, and you don't have dynamic content pushing the layout about as it loads it in your page header, you'll likely get a high CLS score as it has some leeway.
And sounds like `font-size-adjust` from the OP is helpful in avoiding layout shift when the stand-in font is swapped out for the custom font when it arrives? I haven't found this necessary though.