[v3 beta] Edited book covers, authors, narrators and collections revert immediately after saving

On the v3 beta web portal I upload a new cover image and confirm with the check mark (or Ctrl+Enter). The cover snaps straight back to the original. Reopening the edit dialog shows the new cover, but a page refresh shows the old one again. The same thing happens when editing authors, narrators and collections; doing it from the classic UI works.

Resolution: This was a client-side form bug in the v3 beta, not a server or cache problem: React Hook Form did not play nicely with the React compiler, so edits were kept in local form state and never persisted. It is fixed in the v3 beta release published shortly after the report, so pull the latest web-v3.0.0-beta image and hard-reload the page (Ctrl+Shift+R) to clear the cached JS bundle. Until you upgrade, the classic UI is a working fallback for cover, author, narrator and collection edits. If edits still revert after upgrading, verify you are actually on the new build rather than a cached one.