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TypeError: value is not a non-null object 503

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  • 1 has this problem
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  • Last reply by cor-el

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Hi Every time I open Nightly a small window opens saying ( TypeError: value is not a non-null object 503) Then I press OK to the massage and Nightly opens. The problem is with the Facebook toolbar button but I never had the problem till a few weeks ago.

Thanks

Hi Every time I open Nightly a small window opens saying ( TypeError: value is not a non-null object 503) Then I press OK to the massage and Nightly opens. The problem is with the Facebook toolbar button but I never had the problem till a few weeks ago. Thanks

All Replies (1)

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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

If there is a problem with an extension then you will have to wait for an update and disable the extension for now.