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"Error: TypeError: Preferences.get is not a function" keeps popping up when opening Firefox.

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  • 3 have this problem
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  • آخرین پاسخ توسّط cor-el

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The replies to previos inquiries by other users don't explain how to fix problem, they just say to open safe mode.

The replies to previos inquiries by other users don't explain how to fix problem, they just say to open safe mode.

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What is your homepage? (Web page which open first, with Firefox)

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This issue can be caused by an extension that isn't working properly.

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

  • Do NOT click the Reset button on the Safe mode start window or otherwise make changes.
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It opens with Google as the homepage.

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Do you have the "Default Tab" extension?

  • Tools > Add-ons > Extensions