1386869 - Ghost windows on Twitter

Status: RESOLVED INCOMPLETE

(Core :: DOM: Core & HTML, defect)

Description

[Andrew McCreight [:mccr8]]

I'm seeing ghost windows locally with Twitter.

I can sort of reproduce it. The steps are something like:
1. Open Twitter (logged in), scroll down a bit, click on a tweet to bring up the card for it.
2. Click away the tweet, then click on notifications, and close the tab not too much later.

There was a regression in ghost windows at some point between July 11 and July 29, when ghost window telemetry was re-enabled. Maybe this is is related.

Comment 1

[Andrew McCreight [:mccr8]]

Note that this is basically the same STR as bkelly's bug 1277376. :)

Comment 2

[Andrew McCreight [:mccr8]]

In a local session, I had two leaking windows. One was being held alive due to a missing reference to the window itself, while the other was being held alive via a promise.

0x7f5a71e22f40 [Promise]
    --[mPromiseObj]--> 0x7f5a5d7252e0 [JS Object (Promise)]
    --[group_global]--> 0x7f5a64109060 [JS Object (Window)]
    --[CLASS_OBJECT(Object), CLASS_OBJECT(Function), **UNKNOWN SLOT 175**]--> 0x7f5a7257dc00 [JS Object (Proxy)]
    --[private]--> 0x7f5a7257d2c0 [JS Object (Proxy)]
    --[group_global, private]--> 0x7f5a64109100 [JS Object (Window)]
    --[UnwrapDOMObject(obj)]--> 0x7f5a7460f000 [nsGlobalWindow # 4294967461 inner https://twitter.com/i/notifications]

    Root 0x7f5a71e22f40 is a ref counted object with 1 unknown edge(s).

Not too useful.

Comment 3

[Ben Kelly [:bkelly, not reviewing]]

In this case you are closing all twitter tabs, right?

In bug 1277376 a twitter tab must still be open because they are holding disconnected iframes alive via content js references.

Comment 4

[Andrew McCreight [:mccr8]]

(In reply to Ben Kelly [:bkelly] from comment #3)
> In this case you are closing all twitter tabs, right?
> 
> In bug 1277376 a twitter tab must still be open because they are holding
> disconnected iframes alive via content js references.

Yes, I am closing them all. Yeah, the steps aren't identical, they just also clicking on the notifications.

Comment 5

[Andrew McCreight [:mccr8]]

I'm having a lot of trouble reproducing this consistently. I'm not sure why. Closing the tab while it is still loading seems to be required, so maybe that makes it flakey. I think I've reproduced it on builds going back to June 23, so it seems like it may not be the cause of the regression on telemetry.

Comment 6

[Eric Rahm [:erahm]]

Feel free to reopen if you see it again.