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New pop up window Javascript error, Could not initialize dlwatch extension, oPref.addObserver is not a function. Stops new windows from launching. Help.

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  • Last reply by Sin717

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Running Firefox 4 on McabookPro, OS 10.6.7. When a new pop up window open, which is needed for some security apps, I am getting a Javascript error. It says:

[Javascript error] dlwatch(200) Could not initialize dlwatch extension TypeError: oPref.addObserver is not a function.

Running Firefox 4 on McabookPro, OS 10.6.7. When a new pop up window open, which is needed for some security apps, I am getting a Javascript error. It says: [Javascript error] dlwatch(200) Could not initialize dlwatch extension TypeError: oPref.addObserver is not a function.

Chosen solution

That is a problem with the Video DownloadHelper extension.

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Appearance/Themes).

  • Don't make any changes on the Safe mode start window.

See:

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Chosen Solution

That is a problem with the Video DownloadHelper extension.

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Appearance/Themes).

  • Don't make any changes on the Safe mode start window.

See:

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Disabling the VideoDownloader didn't help, but disabling all extensions did. As I don't have very many extensions, I disabled all of them except for Forecast Fox. The main two additional disabled were reminderFox and Public Fox. With those off, problem solved. Thanks so much.

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I had this problem also i disabled Public Fox and now my windows pop up fine.