I am using the PerformanceObserver API in a web extension to get the PerformanceNavigationTiming.
this.performanceObserver.observe({ type: "navigation", buffered: true })
I have several users that installed my extensions and globally I have good value. However, I saw that from time to time I receive wrong values. Here an example:
{
"name": "anonymized",
"entryType": "navigation",
"startTime": 0,
"duration": 1618111,
"initiatorType": "navigation",
"nextHopProtocol": "http/1.1",
"workerStart": 0,
"redirectStart": 1617474,
"redirectEnd": 1617474,
"fetchStart": 1617474,
"domainLookupStart": 1617474,
"domainLookupEnd": 1617474,
"connectStart": 1617474,
"connectEnd": 1617474,
"secureConnectionStart": 1617474,
"requestStart": 1617481,
"responseStart": 1617573,
"responseEnd": 1617573,
"transferSize": 8380,
"encodedBodySize": 7609,
"decodedBodySize": 37651,
"serverTiming": [],
"unloadEventStart": 1617578,
"unloadEventEnd": 1617578,
"domInteractive": 32,
"domContentLoadedEventStart": 91,
"domContentLoadedEventEnd": 93,
"domComplete": 1618094,
"loadEventStart": 1618094,
"loadEventEnd": 1618111,
"type": "reload",
"redirectCount": 0
}
There are 2 facts that make me doubt about the validity of this PerformanceNavigationTiming:
- The duration reported is over 25 minutes, and this is unlikely
- Checking the MDN PerformanceNavigationTiming page, it shows that the domContentLoadedEventStart and domContentLoadedEventEnd are happening in the processing block, almost at the end of the navigation cycle. However, here we have a really low values, respectively 91 and 93.
Do you know if I am missing something? Or maybe is there a bug on the API?
Thanks
