Defer mounting heavy sheet content until the enter slide finishes (revealed on
the slide's transitionend, with a timer fallback) so the animation no longer
competes with a large content render. Shorten the slide to a quick rise from a
small offset, and seat the sheet a few px below the top safe area.
Revert the 100dvh sizing back to inset-0/100% — it did not fix the bottom inset
and reintroduced intermittent top safe-area dimming.
Bohdan Triapitsyn
b692c44562