This also appears to affect elements positioned in other ways as shown:

position: relative; - https://jsfiddle.net/Ln4tqxkx/2/

position: fixed; - https://jsfiddle.net/Ln4tqxkx/3/

This bug only appears to occur if the element animated with a transition is defined before the video in the HTML.

https://jsfiddle.net/Ln4tqxkx/4/

Unable to reproduce the issue on Windows 7, Mac 10.11.5, Ubuntu 14.04 using 50.0.2661.102, latest stable 51.0.2704.84, canary 53.0.2761.2 with below steps:

1.Opened URL: https://jsfiddle.net/Ln4tqxkx/4/
2.Not observed any flickering in video.

gammesoft@: Could you please check the issue on clean profile and update the thread with actual behavior screencast if issue still persists.

ALL URLS POSTED ARE UNIQUE.

Notice that each JSFiddle is for a separate aspect of the issue.  Each URL is unique.  The last URL for example shows a case when the issue does not appear to be problematic.

Consider this additional unique URL for a demonstration of the issue occurring (hover the cursor over the top box) and when it does not (hover the cursor over the bottom box) on the same page.

https://jsfiddle.net/Ln4tqxkx/5/

Thank you for providing more feedback. Adding requester "ssamanoori@chromium.org" for another review and adding "Needs-Review" label for tracking.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The bug as reported happens beacause the video becomes composited due to assumed-
overlap with the animated element.

If you add will-change: transform to the video you can reproduce the same problem
without animations. Example:

https://jsfiddle.net/Ln4tqxkx/6/

I think this may have regressed recently. Perhaps https://blink.lc/chromium/commit/?id=cf4e52129f8305d7c1f938da837ba1db80bf201c. Requesting bisect.

Tested the issue on Windows 7, Mac 10.11.5, Ubuntu 14.04 using 50.0.2661.102, latest stable 51.0.2704.84, canary 53.0.2762.0 with below steps:

1.Opened URL: https://jsfiddle.net/Ln4tqxkx/5/
2.Hovered the cursor over the top box.
3.Observed that screen blinked to another screen and to original in a second(as in attached screencast).
4.Observed that no blink or change of screen in firefox.

Please find attached screencast of chrome, firefox behavior.

gammesoft@Could you please provide actual and expected behavior screencast for further triaging the issue.

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	617642.mp4 779 KB View Download

Tested on Mac OS 10.11.15 with Chrome version 50.0.2661.102 (64-bit).

1. Opened URL https://jsfiddle.net/Ln4tqxkx/5/
2. Hovered over top div
3. Observed that user poster was replaced by automatically generated video poster during transition
4. After the transition ended the user poster reappeared
5. Hovered over the bottom div
6. Observed no change to the video poster

Deleted: Issue 617642.mp4 1.4 MB

	Issue 617642.mp4 1.4 MB View Download

Expected behavior occurs in Firefox.  Following the same steps on the same URL as the previous video.

Deleted: Issue 617642.mp4 764 KB

	Issue 617642.mp4 764 KB View Download

Thanks for the update.

Able to reproduce the issue on windows 7, Linux Ubuntu 14.04 and Mac 10.11.5 using chrome version 51.0.2704.84 and canary 53.0.2766.0.

This is non regression issue as the issue seen from till M36 builds.M35 and prior builds not performing the hover effect.
Marking it as Untriaged to get more inputs from dev team.

removing bisect label.

Thanks,

Moving this nonessential bug to the next milestone.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

When will this issue be fixed?  It looked like it was slated for the 54 release of Chrome.  However, Chrome has already released version 56.

To cause the glitch, the property transitioned must be "transform". In this example: https://jsfiddle.net/ag4nuo3g/1/, transitioning only the background, the video stays untouched.

This still isn't fixed on Chrome 60.

This appears to be fixed as of Chrome 69.