Navigate to: https://httpbin.org/redirect-to?status_code=307&url=/
performance.timing.redirectEnd > performance.timing.requestStart In Chrome it returns true, in other browsers false.

+npm@, could you take a look?

The Navigation Timing spec [1] says

"The following graph illustrates the timing attributes defined by the PerformanceTiming interface and the PerformanceNavigation interface with or without redirect, respectively. Attributes underlined may not be available in navigation involving documents from different origins. User agents may perform internal processing in between timings, which allow for non-normative intervals between timings."

redirectEnd is underlined so if I'm interpreting correctly it is an optional attribute? And if present, does redirectEnd need to be <= requestStart? Maybe the NavigationTiming experts can answer that.

[1] https://www.w3.org/TR/navigation-timing/#process

It is optional.
We set requestStart in step 13.
We set redirectEnd in step 16, but then return to step 6 with a new resource, without clearing redirectEnd.

My understanding is that this implies redirectEnd must be less than requestStart, if present.

Any update ?

No updates yet, I haven't figured out how to fix this.

Do you know what caused this to happen ?

It looks like the redirect is not properly triggering a new requestStart. Did this work properly for you on a previous version of Chrome? If it worked before, we can bisect to find the cause. But my guess is that this has never worked properly.

I ran Chromium 48 and I see the same behavior there.
However, there is no problem on Mac.
I'll try older Chromium , hopefully find something.

I checked Chromium 30 and it works fine there.

Ok, thanks for looking into it! Such an old problem is probably not worth bisecting, but I'll look into the problem when I get a chance.

I'll be away from speed-metrics a month, reassigning to tdresser@.

It seems that this bug is not only with redirectStart but with other measurements.

When I go to
https://httpbin.org/redirect-to?status_code=307&url=/ 

performance.timing.domainLookupStart>performance.timing.requestStart
true
performance.timing.domainLookupEnd>performance.timing.requestStart
true

https://www.w3.org/TR/navigation-timing/timing-overview.png

Deleted: timing-overview.png 61.4 KB

	timing-overview.png 61.4 KB View Download

I'm not going to get to this before npm@ gets back.

Any update ?

I think this has been fixed recently, probably by yhirano@. nn1436401@ can you check if that's the case for you on dev channel? I tested 68.0.3432.3 on Linux.

Sorry or was it kinuko@ with https://chromium-review.googlesource.com/c/chromium/src/+/974673? I feel like there have been several fixes to nav timing recently so not sure what fixed this bug.

Ping. Any update?

This is fixed. I didn't hear back from bug reporter to confirm.