Macintosh OS/Firefox


I just updated Firefox on my Mac OSX 10.8.4 and it has started to bug me by freezing accompanied by the following pop-up:

[JavaScript Application]
evalInSandbox:SyntaxError: syntax error

I click OK and it recurs immediately, about 6 to 16 times before I can use Firefox. Then it starts again within a minute or so.

Iíve no idea why this is happening.  Can you help?


It sounds like an extension in firefox may be giving you problems.

Take a look at this document on troubleshooting firefox:

There is a "safe mode" - if the problem goes away, it's due to some extension you installed.

Some people have reported this is with an older version of "Social Fixer" extension. You need to update this if it's the case.

Macintosh OS

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Jeff Greenberg


I can comfortably answer most basic/advanced questions regarding Macintosh hardware and software - nowadays only OSX. In fact, if it's prior to 10.3, there's a good chance I'll reject your question. Forget OS9 stuff - Igave up OS 9 ten years ago). Please do not ask me about OS9. My particular specialties are in Video editing/DVD authoring. I am a certified trainer in the "pro apps" (Final Cut, DVDSP, Soundtrack, Motion). I have been using Macs since 1985.


I'm an Apple Cert. Trainer for FCP, DVD SP, since the inception of this program. I've was
certified as an Apple Cert. Technician back in 1989.

Videography, Macworld, Tibits

BA film- Penn State. Certifications from Apple, Adobe and Avid for training.

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