docs: the superseded fallback answers its own session; who uses beacon()

2026-10-08 01:16:30 +02:00
parent 5095047c81
commit a504550196
2 changed files with 9 additions and 7 deletions
@@ -285,11 +285,12 @@ export function identityHeaders(): Record<string, string> {
  };
 }

-// Fire-and-forget POST that survives page unload (keepalive) — shared by the resume-position
-// beacons (YT + Plex players). A normal fetch is cancelled on unload and React effect cleanup
-// doesn't run on a full reload, so without keepalive the last position (esp. right after a seek)
-// would be lost. `onSettled`: the request has been answered (or failed) — for a caller whose cached
-// view must be read again once the write is on the server.
+// Fire-and-forget POST that survives page unload (keepalive) — for every write a closing page must
+// still make: the resume checkpoints of the YouTube, Plex and library players, the Plex session stop,
+// the diagnostics flush. A normal fetch is cancelled on unload and React effect cleanup doesn't run
+// on a full reload, so without keepalive the last position (esp. right after a seek) would be lost.
+// `onSettled`: the request has been answered (or failed) — for a caller whose cached view must be
+// read again once the write is on the server.
 export function beacon(url: string, body: Record<string, unknown>, onSettled?: () => void): void {
  try {
    void send(url, {