1249495 - Flicker on initial hover on image with fresh cache.

Status: RESOLVED DUPLICATE of bug 1225934

(Core :: Layout: Images, Video, and HTML Frames, defect)

Description

[hello]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:46.0) Gecko/20100101 Firefox/46.0
Build ID: 20160218004005

Steps to reproduce:

Regular Firefox 44 does not show it. The issue was discovered in WordPress core but decided to report the issue here instead. See https://core.trac.wordpress.org/ticket/35789

1. Open FirefoxDeveloperEdition 46.0a2
2. In a WordPress install, to to Appearance>>Themes within wp-admin 
3. Refresh the page and bypass the browser's cache. (Mac cmd + shift + R)
4. Hover theme screenshots.


Actual results:

See screencast: http://quick.as/9yj2sooqn


Expected results:

Images should not flash when bypassing the cache.

Comment 1

[Michelle Funches - QA]

Setting to Core: Layout
No server or WordPress account so this was not reproduced

Comment 2

[hello]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:46.0) Gecko/20100101 Firefox/46.0
Build ID: 20160218004005

New Steps to reproduce:

Refresh the page and bypass the browser's cache. (Mac cmd + shift + R)

1. Visit demo: http://s.codepen.io/fusco/debug/ZQmmox
2. Refresh the page and bypass the browser's cache. (example: Mac cmd + shift + R)
3. Hover over the images. Sometimes it takes 2 or 3 hovers to see the flash. Once it happens, it will only happen again if the browsers cache is bypasses again or reset.

Comment 3

[hello]

First time using this system. Wasn't done editing the above comment and accidentally hit save. Doesn't look like I can delete or edit my comment anywhere. Here is the intended comment:

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:46.0) Gecko/20100101 Firefox/46.0
Build ID: 20160218004005

New Steps to reproduce:

1. Visit demo: http://s.codepen.io/fusco/debug/ZQmmox
2. Refresh the page and bypass the browser's cache. (example: Mac cmd + shift + R)
3. Hover over the images. Sometimes it takes 2 or 3 hovers to see the flash. Once it happens, it will only happen again if the browsers cache is bypasses again or reset.

Comment 4

[Michelle Funches - QA]

@Reporter - thank you for the update. 

Setting status to new as I have confirmed this.
Reproducible: 
Version 	46.0a2
Build ID 	20160219004008
User Agent 	Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:46.0) Gecko/20100101 Firefox/46.0

Comment 5

[Loic]

Thanks for the testcase because Wordpress is so SLOW to display all the themes on the same page. 
It's a regression in FF45+ by Bug 1207355:

https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=99a4fb4ba5c1ee96ac745c6ad11894bf0537f73a&tochange=2e19045ba652ca2a5a5fc0e20d6f95293acfa32d

NI to tnikkel instead of Seth.

Comment 6

[Liz Henry (:lizzard) (relman/hg->git project)]

Tracking for 46+. 
Regression from 45 but seems unlikely to be fixed in time for uplift to 45.

Comment 7

[Liz Henry (:lizzard) (relman/hg->git project)]

Wontfix for 45 and 46 since this is still unassigned, so we will ship with this regression. 
But if anyone does come up with a patch, please request uplift to 46.

Comment 8

[Jet Villegas (inactive)]

This one's also fixed by bug 1225934. Uplift requested there.

Comment 9

[Virtual_ManPL [:Virtual] 🇵🇱 - (please needinfo? me - so I will see your comment/reply/question/etc.)]

Per Comment #8.