Note: There are a few cases of duplicates in user autocompletion which are being worked on.

jank when opening a google groups page




JavaScript Engine
5 years ago
a year ago


(Reporter: timbugzilla, Unassigned)



Windows 8

Firefox Tracking Flags

(Not tracked)




(1 attachment)



5 years ago
Created attachment 663634 [details]
about:support as text file

I experience a few seconds of jank when opening a google groups' group page such as

A gecko profiler profile for this is available here:

My about:support has been attached as a text file.
Component: General → General
Keywords: perf
Product: Firefox → Core

Comment 1

5 years ago
I notice this on x64 Windows 7 on all Google Blogspot blogs that use widgets and default themes.

Comment 2

5 years ago
Here's a profile for opening the "my groups" page at google groups.

Most of the jank period seems to be spent in an Evaluate String operation.

Profile was recorded on an Intel E8500 based machine with win7 x64. 06/02 moz-central nightly win32 build.!myforums


5 years ago
Component: General → JavaScript Engine

Comment 3

5 years ago
even opening the gmail page for the first time causes ~1-1.5 seconds jank.
Profile :

IIRC this is already being tracked in another bug. Should be P1, IMO.

Comment 4

5 years ago
see also : bug 789598

Comment 5

5 years ago
There is also quite a bit of jank when using the "u" keyboard shortcut to return to group page from a thread page. e.g. Go to the group:!forum/

Then enter the thread for "How does one debug uninitialized value usage from JavaScript (TB) ?".!topic/

Then press the "u" key to return to the group.

I do not see this when using the same keyboard shortcut to return to my inbox in gmail for example. The operation also completes a lot more quickly in Chrome.

The profile is here:

Most of the jank time seems to be spent in the JS interpreter.

Comment 6

5 years ago
That profile was recorded on an Intel E8500 based machine running todays moz central nightly win32 build, on win7 x64.

Comment 7

5 years ago

In google groups, switching from "compact list view" to "standard view".
Can you still reproduce?!topic/ takes a long time to load. But I do not experience jank. This is with a current nightly and e10s enabled, heavily loaded with 400 tabs

I also cannot reproduce related bug 924001, nor bug 802731
Flags: needinfo?(timbugzilla)
Flags: needinfo?(mayankleoboy1)

Comment 9

2 years ago
with e10s and APZC, this is fine now.
Flags: needinfo?(mayankleoboy1)

Comment 10

2 years ago
Looks like there is still a little bit of jank (like less than 500 ms), but it is much better.
Flags: needinfo?(timbugzilla)
Thanks for the update
Last Resolved: a year ago
Resolution: --- → WORKSFORME
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