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HTTP/1.1 · Connection: close
HTTP/1.1 · keep-alive
HTTP/2
HTTP/2 + preconnect
TCP connections opened
3
Handshakes on the critical path
2
Estimated total time
570
ms
Time
TCP/TLS handshake
preconnect
Server wait (TTFB)
Download
Queued / blocked
What the browser does under the hood