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Firefox 18 breaks my website in a bad way


I have a very Javascript-heavy website, utilizing Backbone, Underscore, jQuery (1.8.3), Isotope and the GreenSock animation library. From Firefox 15 to version 17 my website worked great, regardless of platform. I should start off noting that my JS has 0 lint-errors and I've tested thoroughly on Windows XP, Windows 7 and OSX using all previous noted versions of Firefox (along with 18). All other browsers (including WinXP IE8) load the site just fine but Firefox 18 (regardless of platform) not provides me with super inconsistent behavior on this site. On one load everything will work great, on the next refresh the site doesn't work at all, on the next refresh it won't work but on the on thereafter, it will work. I cannot seem to drill down what is causing this and have spent all day digging for something only to come up empty handed. Does anybody have any insight what may be causing this? Could this be a bug in either a major library or a bug in Firefox's new JS engine causing this?

Additional System Details


  • User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_5) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.101 Safari/537.11

More Information

All major platforms, Windows XP, 7 and OSX have this issue with Firefox 18.

panpur 0 solutions 1 answers

I have a very Javascript-heavy website too, but built using ExtJS. Works fine on other browsers & FF 17, but broken on FF 18.

It seems this is Firefox bug?

Question owner

I am starting to think so. I have tried console logging out each line of the statements in question and they all will spit something out. It is just for some reason, Firefox choses to skip over chunks of code for no reason. I simply cannot place my finger on what it is, other then something with the browser or it's fancy new Iron Monkey. I've tested on Firefox 15, 16 and 17 and the website works perfectly on all platforms. Upgrade platforms to 18 and all of a sudden the problems start.

Swarnava Sengupta 482 solutions 3135 answers

Helpful Reply

If you think its a bug, can you please file a bug at bugzilla.mozilla.org ?

Swarnava Sengupta 482 solutions 3135 answers

so wait sometime, someone from fxdev will try to reproduce and will let you know if its Firefox bug or your page :)

Safe Surf

Severe Tech 0 solutions 1 answers

Helpful Reply

I'm another person having a very similar problem, but I found that even the almighty RocketTheme has demo templates that turned up looking wrecked after I upgraded to Firefox 18. I verified the same results from multiple PC's. Not only does the problem occur, but it is very consistent and happens 100% of the time. It looks as if Firefox turned up a caching method which strips the capability for javascript style sites to load correctly.

Examples: Rockettheme Template: http://demo.rockettheme.com/may11/ My Business Website: SevereTech.com