The sidebar reports a profile it could not scan as HTTP 200 with an empty
page and errors=[{profile}]. The renderer merges that page keeping only
working, pinned, and selected rows, so every idle Yesterday / This-week
session disappears until a later scan succeeds — and the 5s coalescing cache
then serves the same empty payload back for the rest of its TTL.
Carry the previous rows forward for exactly the profiles named in errors[],
keyed by profile::id so a twin id in another profile is never stitched in.
Profiles that scanned cleanly are still authoritative, so a genuinely empty
page with no errors still clears the list. Per-profile usage and truncation
flags follow the same rule rather than zeroing under a list that was kept.
The legacy per-slice fallback stamps errors on the slice that actually
failed, so a cron read failure can no longer blank recents.
Part of #73847
Part of #88528
Co-authored-by: AKAZIK-py <AKAZIK-py@users.noreply.github.com>
Brooklyn Nicholson
3d81650c2f