1372532 - Private window: Finite length animation is blocked

Status: RESOLVED DUPLICATE of bug 1388733

(Core :: Graphics: ImageLib, defect, P3)

Description

[roxleitan]

Attachment: test gif iframe.html

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:56.0) Gecko/20100101 Firefox/56.0
Build ID: 20170612091112

[Affected versions]:
Nightly 56.0a1

[Affected platforms]:
Windows 10 x64

[Steps to reproduce]:
1.Launch Nightly 56.0a1 with a new profile
2.In a new private window open the attached HTML
3.Open a new tab in the window opened at step 2
4.Open a new private window and navigate to about:memory
5.Click "Minimize memory usage" button
6.Go to the tab with the animation (opened at step 2)

[Expected result]:
The animation from all frames should be displayed without glitches.

[Actual result]:
In the second iframe, the animation is blocked.

[Note]:
The issue is intermittent and I could reproduce it only in private window.

Comment 1

[Timothy Nikkel (:tnikkel)]

Is this a regression from bug 686905? Have you tried reproducing in builds before bug 686905 landed?

Comment 2

[roxleitan]

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:56.0) Gecko/20100101 Firefox/56.0

I tested using Nightly 55.0a1 (Build ID: 20170407030233 - before bug 686905 landed) and I couldn't reproduce it.

And tested again with the latest Nightly 56.0a1 (Build ID:20170615030208) and reproduced the issue.

Comment 3

[Andrew Osmond [:aosmond] (he/him)]

How intermittent is it? Is it possible to provide a video of your reproduction to confirm the steps? I was unable to reproduce on 2016-06-13, 2016-06-15 nor 2016-06-23 nightlies following the STR after many attempts. Note for the imgur animated images to show up at all, I had to download the test case locally and point the imgur URLs to a local copy.

Comment 4

[roxleitan]

Attachment: animation_blocked.mp4

Hi Andrew,

I tested with the latest Nightly (2017-06-23) on Mac OS X 10.12 using the HTML saved on my computer and managed to reproduce the issue.(3/10 attempts) (please see the "animation blocked" screencast.

It seems that the issue is reproducible only while the page is still loading.

Comment 5

[Timothy Nikkel (:tnikkel)]

I was able to reproduce this on my computer a few times with Roxana's help. It seems to be important that the page is still loading when you minimize memory _and_ when you change back to the tab.