SSE Tap

Read every Server-Sent Event your page receives — full payloads, refresh history, in its own tab.

SSE Tap records the Server-Sent Events your page receives and shows them in a normal Chrome tab you can leave open on a second monitor. It exists because the DevTools EventStream tab does three things badly: - Payloads get truncated. SSE Tap captures messages whole up to 1MB, renders them in full, and lets you expand and copy any one of them. - Events that fire before you open DevTools are gone. SSE Tap collects from document_start in the background, so the events your app emits during startup are already recorded when you go looking. - A refresh wipes the log. SSE Tap's buffer carries across reloads, and marks each reload inline, so you can read before and after as one timeline. Gaps in the stream are called out where they happened, so "the event never came", "the connection died and quietly reconnected" and "the page reloaded before it arrived" stop looking alike. Nothing to add to your app — no import, no script tag, no console paste. No data ever leaves your browser. Needs Chrome 111 or newer.