Examining a WPT test /scroll-animations/css/scroll-timeline-in-container-query.html, it seems that we aren't quite aligned on this.
It seems that WebKit expects the animation to have an inactive timeline until the next animation frame, but Blink does not.
A potentially related question is that when a scroll timeline becomes valid, what its scroll snapshot looks like until they're updated in the Resize Observer loop - is it at (0, 0), or should it try to take the scroll position, if available?
I also derived a testcase avoiding container query, just to remove interleaving as a potential source of weirdness - Seems that we still diverge.
... I don't think spec really elaborates on this, unless I'm missing something.
Examining a WPT test
/scroll-animations/css/scroll-timeline-in-container-query.html, it seems that we aren't quite aligned on this.It seems that WebKit expects the animation to have an inactive timeline until the next animation frame, but Blink does not.
A potentially related question is that when a scroll timeline becomes valid, what its scroll snapshot looks like until they're updated in the Resize Observer loop - is it at (0, 0), or should it try to take the scroll position, if available?
I also derived a testcase avoiding container query, just to remove interleaving as a potential source of weirdness - Seems that we still diverge.
... I don't think spec really elaborates on this, unless I'm missing something.