Opened an anchor bug a couple weeks ago. The most bizarre thing was happening with the auto flip feature of anchor positioning.
or so I thought…
prob #
When I had like > 1000px
viewport, the anchored element would flip-block
like I wanted. But… when I went to smaller viewports, it just stopped working.
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What in the world does the width have to do with anything?
There was ample space around the anchors for the positioned element to occupy, at least it seemed.
solution #
The solution didn't end up having anything to do with flip-block logic. It was my usage of position-area: top center;
.
.floaty {
position-area: top center;
}
An engineer (a rad one) replied:
So this is a danger of using the "center" position-area. The anchored element doesn't fit. E.g. its inline size is larger than the area. In this case we just bail and use the first. If you switch to position-area: top it works as expected. We need better devtooling to help explain this :(.
chromium.org/issues/360921604
and sure enough, switch the line of code to
.floaty {
position-area: top;
}
Fixed. Width no longer effects anchor flip.
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dang.
So I guess I need to understand more about "the danger of using position-area: center
" 👀
The fixed experience.