1453753 - Ghost windows on PC Gamer and Google Docs

Status: RESOLVED DUPLICATE of bug 1451985

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

Description

[Andrew McCreight [:mccr8]]

I've seen some ghost windows in the recent Nightly. The earliest build I actually noticed this was April 10, though I can reproduce it on a 4-12 build as well. Originally, on the April 10 build, I was getting something like hundreds of them for this URL: https://www.pcgamer.com/hearthstones-ben-brode-if-you-knew-how-good-a-card-is-by-looking-at-it-we-wouldnt-need-a-balance-team/

Also for a Google Docs page. I can kind of reproduce the ghost window for PC Gamer on the latest Nightly, but I don't have good STR nailed yet. Sometimes it leaks, sometimes it doesn't. Maybe there's a particular ad that causes it, or maybe you have to close the page in the middle of loading in just the right way.

The CC log results looks like this:

0x1561387c0 [FragmentOrElement (xhtml) script https://www.pcgamer.com/hearthstones-ben-brode-if-you-knew-how-good-a-card-is-by-looking-at-it-we-wouldnt-need-a-balance-team/]
    --[GetParent()]--> 0x13363ff00 [FragmentOrElement (xhtml) body class='limit-width limit-width  no-touch' https://www.pcgamer.com/hearthstones-ben-brode-if-you-knew-how-good-a-card-is-by-looking-at-it-we-wouldnt-need-a-balance-team/]
    --[]--> 0x1630f2940 [nsDOMMutationObserver]
    --[mOwner]--> 0x1514afc00 [nsGlobalWindowInner # 6442450978 inner https://www.pcgamer.com/hearthstones-ben-brode-if-you-knew-how-good-a-card-is-by-looking-at-it-we-wouldnt-need-a-balance-team/]

    Root 0x1561387c0 is a ref counted object with 1 unknown edge(s).
    known edges:
       0x13363ff00 [FragmentOrElement (xhtml) body class='limit-width limit-width  no-touch' https://www.pcgamer.com/hearthstones-ben-brode-if-you-knew-how-good-a-card-is-by-looking-at-it-we-wouldnt-need-a-balance-team/] --[mAttrsAndChildren[i]]--> 0x1561387c0

So, something is holding onto a script element. I've seen things like this off and on before, but not as consistent of this.

I don't see any ghost windows or increases in CC pause time in Telemetry so hopefully it isn't a wide spread issue like the thing Ben recently fixed.

Comment 1

[Ben Kelly [:bkelly, not reviewing]]

Looks like the trace I got in bug 1451985 which was also somewhat reproducible.

Comment 2

[Andrew McCreight [:mccr8]]

I may end up just duping this over to bug 1451985.

Comment 3

[Andrew McCreight [:mccr8]]

I'm going to dupe this to bug 1451985. The CC log looks similar, and this is hard to reproduce so it is hard to say for certain.