I may have to give up on getting my site to work on FireFox. I sure do wish the people who design or "upgrade" web browsers would use some common sense....and realize that what they do can have a negative effect on a lot of people.

I would expect this kind of behavior from IE, but I can now confirm that animated .gif files (when used as rollovers) do not function properly in FF 4.0.1 (Mac). See: http://bommars.com/ for an example, and PLEASE FIX THIS!!!

Yes! Thanks for the support and confirmation.

Firefox by default will run animated gifs normally. Either the image.animation_mode preference got changed or a external software may be stopping .gif image animations.

http://kb.mozillazine.org/Animated_images

The animated gifs on bommars.com works for me.

@ James:

The animated gifs on bommars.com do not work for me (using Firefox), and I have checked my settings and they are on default (normal).

You might want to see how the site looks on Safari because there it works correctly.

You understand, I hope, that we are talking about animations repeating? In other words, if you have an animation that is supposed to play no a roll-over, it should play every time you rollover it. But Firefox seems to say that once something has played it won't play again.

But actually on bommars.com I can't even get the animations to play once with any consistency. But it plays fine on Safari and Opera.

See this bug report (fixed on trunk - Firefox 6)

• Bug 641198 - Rollover animated gif show only one frame

I designed bommars.com less than a year ago during the FF 3.x (Mac) era. At that time, the animated .gif rollovers (which are designed to play one time rather than loop) worked properly in the then-current release versions of FF (Mac), Safari (Mac), FF (Windows), and IE (Windows). When I went to update the site yesterday, I noticed the malfunctioning animated .gif files in FF--but not in Safari; I haven't had a chance to see if this is also an issue with the latest release version of FF for Windows...

I am using a Mac, and I did not modify any about:config preference (e.g., image.animation_mode). I am also not using Norton Internet Security, ZoneAlarm Pro, or eTrust Firewall. The only FF Add-On I use is FireFTP, but the animated .gif issue persists even when it is disabled or uninstalled.

To reiterate, the rollover animations continue to work properly in FF 3.x (Mac), but they are not functioning as expected in FF 4.0.1 (Mac).

I have no reason to believe that this is anything but a FF 4.x (Mac) bug.

One other observation: in Firefox 4.0.1 (Mac), the local copy of my animated .gif files consistently work properly via the "Open File..." menu. Can anyone explain why this would be possible?

Interesting. I don't know enough about the Firefox browser to know why that would happen.

As far as I know this issue has still not been resolved.  :(

I'm not pleased to find Firefox which I had decided to use recently does this and might have to go back to Windows Explorer 8 as I it was working fine and had only changed to Firefox, because some downloads I could not download wouldn't download.

@pmayor, Based on the date of fix (after 4.0 release) on the then Trunk it should be fixed on Firefox 5.0 and newer.

At the time that I posted my above response the bugzilla reports still had a target milestone that showed Firefox 6 for that bug or I wouldn't have posted that. That target appears to have gone now, so you would have to verify the checkin range for 5 and 6 to see where it ends up.

Thanks for the responses. I'll download the latest version and check it out. Much thanks.