The attached files should have a black square at the top of the document, and a blue square almost at the bottom. The black square is not rendered in Chromium, probably because we don't map the rectangle such that we realize we need to paint the <div>.

This is only apparent when there is an offset (e.g. for drop-shadow or <feoffset>) that is large enough to span the pre-paint distance (currently viewport + 4000px), which is why this effect is not apparent in real-world sites.

Firefox renders this correctly.
 

Deleted: ex.html 172 bytes

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