1526986 - BrowserUsageTelemetry.jsm, line 108: TypeError: win.gBrowser is undefined

Status: REOPENED

(Firefox :: General, defect, P3)

Description

[Florian Quèze [:florian]]

I saw this error today when keeping Cmd+N pressed for a few seconds to open several browser windows at once. It was on this line: https://searchfox.org/mozilla-central/rev/5e3bffe964110b8d1885b4236b8abd5c94d8f609/browser/modules/BrowserUsageTelemetry.jsm#108

I think gBrowser doesn't exist yet because the window hasn't finished initializing. That's likely because Services.wm.getEnumerator("navigator:browser") returns all browser windows, including the ones that aren't done loading.

Comment 1

[Matthew N. [:MattN]]

Dexter, this is potentially skewing our data. Is this something you want to fix or should I mark it P3?

Comment 2

[Alessio Placitelli [:Dexter]]

(In reply to Matthew N. [:MattN] (PM me if requests are blocking you) from comment #1)

Dexter, this is potentially skewing our data. Is this something you want to fix or should I mark it P3?

Hey Matthew, I'm redirecting this to Chris as I'm mostly on glean these days.

Comment 3

[Chris H-C :chutten]

If this is something that only comes up when opening new windows as fast as possible there's no priority from our end :)

Comment 4

[Matthew N. [:MattN]]

Thanks

Comment 5

[Florian Quèze [:florian]]

(In reply to Chris H-C :chutten from comment #3)

If this is something that only comes up when opening new windows as fast as possible

That's the steps to reproduce on a fast development machine.

Normal users may see this whenever opening a browser window is slow.

Comment 6

[Chris H-C :chutten]

So it may affect the recording of browser.engagement.max_concurrent_{tab|window}_count and browser.engagement.tab_open_event_count by undercounting.

ni?rweiss who is the owner of those probes for what impact it might have and whether that should change the priority.

Comment 7

[Harry Twyford]

Chris, this bug came up during Firefox::General triage. Are the probes you mentioned still being recorded and are they still affected by this bug?

Comment 8

[Chris H-C :chutten]

They are still being recorded and are still being used. If this error still manifests, they'll still be affected.

Comment 9

[Mike Conley (:mconley) (:⚙️)]

Hey florian, we tried to reproduce this but no luck. Are you still seeing it?

Comment 10

[Florian Quèze [:florian]]

Attachment: Screenshot of the errors

I reproduced on today's Nightly.

Comment 11

[Florian Quèze [:florian]]

Attachment: Bug 1526986 - ignore windows that have not finished loading when counting tabs for telemetry, r=chutten.