The per-session DetailStore map is page-lifetime, so a store whose Context
tab, sidebar panel, or /context modal had gone kept trailing its own read
schedule: a broken detail route was re-POSTed every 2.4s for the rest of the
page's life with nobody reading the answer (measured on a real session: 2
extra POSTs in the 3s after unmount, unbounded).
The last unsubscribe now parks the store: the armed window is cleared and no
read is armed while nobody subscribes. The cached payload is kept, so a
re-open still renders instantly (measured: identical rendering digest and no
refetch on remount); a resume with nothing cached clears the ledger and the
old backoff, so the mount's own request(rev) reads again instead of sticking
on the retry note.
bowenliang123
45e169749f