Reported on macOS: on a fresh install, pointing at a DLC folder in Settings and
running a scan showed NO songs until an app restart. The scan itself was fine —
_background_scan re-reads config.json fresh, so it scans the new folder and
populates the library — but the v3 Songs grid never reloaded.
The Settings Rescan / Full Rescan handlers only refreshed the classic (v2)
library via loadLibrary(); the v3 grid (static/v3/songs.js) had no listener for
a scan it didn't initiate (only its own upload path self-refreshes via
watchUploadScan). So its cached, pre-DLC (empty) DOM/snapshot survived a sidebar
return until a full reload (restart).
Fix: the rescan handlers now emit `library:changed` (static/app.js). The v3 grid
listens and reloads if it's the active screen, else sets `_libraryDirty` so the
next onV3SongsScreenEnter does a full re-fetch — a short-circuit placed ahead of
every cached-DOM fast-path so it can't restore the stale grid.
Tests: tests/js/v3_library_refresh.test.js guards the emit + the reload/dirty
wiring (DOM/event glue isn't headlessly unit-testable; end-to-end wants an
in-app run of the reporter's flow: set DLC in Settings → scan → Songs populate
without restart).
Claude-Session: https://claude.ai/code/session_01QbexxfTt8q2tAn436MqGWF
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Co-authored-by: byrongamatos <xasiklas@gmail.com>
