When I run a webpagetest on a simplified page, where it has only a css file and couple of images (no JS, no iframes etc), then in the waterfall diagram, i can see that the css was loaded at around 1s mark, the layout and styling related activity in the main thread is done at around 1.3s. but the first paint (which is a a simple body background-color, no animation, no images etc) happens around 1.9s. I'm wondering what causes the half a second delay? Or is it something related to wpt screen recording? because the font and lazy images also start to download around the time where the first layout burst finishes in the main thread. So i would've assumed that that is when the browser has done the layout and knows what fonts are needed or what images are in the viewport.
I think i have seen this gap in the chrome devtools before. But i couldn't reproduce it. What I see is a clear: css is downloaded, then layouting, then first paint. all right after the previous step. (measurement without any throttling being active)
