Maximizing the Coach drawer hands the conversation to /coach and carries
?doc= with it, so browser-Back can rebuild the sheet. That is the one
close-shaped transition whose whole point is to LEAVE the selection where
it is, and the close path has always returned early for it.
The dropped-traversal check added beside that close did not know. It saw
a closed sheet and a selection still in the address bar, which is exactly
the state it exists to repair, and it repaired away the return URL a
quarter of a second after the close had deliberately preserved it.
Whether it won that race was a question about how fast the machine
navigated, so it surfaced as one flaky run on the narrow viewport rather
than as a broken feature.
Both sides read one named predicate now, and the check is skipped when
the close kept the selection on purpose. Proved by driving the grace
window to zero, which is the worst case the timer can have: before, the
maximize never even reached /coach, three attempts out of three; after,
it passes there and the whole documents family passes with it. Twenty
consecutive runs of that family on the narrow viewport are clean.
Closing a card-opened document asks the browser to go back, so the entry
the selection pushed is consumed and the reader's next Back reaches the
page before it. A traversal is a request, not a guarantee: one asked for
while another is still settling can be dropped, and nothing raises when
it is. The sheet closes, React stays consistent, and the address bar goes
on naming a document nobody has open, so a reload or a shared link
re-opens the sheet that was just closed.
Pressing Escape straight after the browser's Forward button is exactly
that shape, and it reproduces: ten repeats across both viewports failed
two of twenty with the URL still carrying the id, and none of twenty once
the close verifies itself. The check is guarded by the document id, so a
traversal that landed on a different selection is left alone, and it is
cancelled the moment the sheet re-opens.
The browser test that found it could not say so. It asserted the sheet
was closed through a locator matched on the document TITLE, and the sheet
falls back to an untitled label while its detail read is pending, so the
assertion also passed on an open sheet showing a skeleton, resolved
immediately instead of waiting, and pushed the failure into a URL poll
ten seconds later. It now asserts the dialog role, which is what the
neighbouring deep-link test already does.
Marc-André Bombeck