539982 - Inconsistent handling of large numbers of javascript onerror events

Status: RESOLVED INCOMPLETE

(Firefox :: General, defect)

Description

[marv-work]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.7) Gecko/20091221 Firefox/3.5.7
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.7) Gecko/20091221 Firefox/3.5.7

I've found that Firefox is a little inconsistent when it comes to handling large numbers of onerror events attached to img tags.

In both http://dev.signpostmarv.name/pub/twitter-avatar-display/really-huge-grid.html and http://dev.signpostmarv.name/pub/twitter-avatar-display/really-huge-grid-data-uri.html , javascript is used to apply a background image when an image fails to load. The former uses a src attribute of "http:" while the latter uses "data:image/png,".

data URIs result in the expected behaviour, though I have suspicions that a really, really big list might still trigger the problem.

using complete urls (e.g. "http://example.org/" instead of "http:" makes no apparent difference.

enabling the cache makes no apparent difference

Reproducible: Always

Steps to Reproduce:
1. Load or refresh http://dev.signpostmarv.name/pub/twitter-avatar-display/really-huge-grid.html
Actual Results:  
Not all img tags that fail to load have a background applied e.g. error event does not fire for all relevant img tags.

Expected Results:  
All img tags that fail to load (regardless of HTTP status code or specified attribute relating to a valid image) have a background image applied.

Number of events fired seems dependant upon free resources/device performance, since there were fewer background images being applied when I was running games etc.

Comment 1

[Ria Klaassen (not reading all bugmail)]

I made a screenshot of what I see: the first is the latest Firefox 3.5, the second the latest trunk nightly build (Minefield) and finally Google Chrome.
http://yfrog.com/0ogridhmj

Comment 2

[Tyler Downer [He/Him]]

Reporter, are you still seeing this issue with Firefox 3.6.13 or later in safe mode? If not, please close. These links can help you in your testing.
http://support.mozilla.com/kb/Safe+Mode
http://support.mozilla.com/kb/Managing+profiles

You can also try to reproduce in Firefox 4 Beta 8 or later, there are many improvements in the new version, http://www.mozilla.com/en-US/firefox/all-beta.html

Comment 3

[Tyler Downer [He/Him]]

No reply, INCOMPLETE. Please retest with Firefox 3.6.13 or later and a new profile (http://support.mozilla.com/kb/Managing+profiles). If you continue to see this issue with the newest firefox and a new profile, then please comment on this bug.