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Need help! "what happened:TypeError: this.installDir is null"

  • 3 replies
  • 47 have this problem
  • 3 views
  • Last reply by Renshi

Renshi
Renshi
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I get this message whenever I open Firefox. I do not get the message when I open Safe Mode with add-ons disabled.

I get this message whenever I open Firefox. I do not get the message when I open Safe Mode with add-ons disabled.

All Replies (3)

TonyE
TonyE
  • Moderator
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That implies that it is one of the add-ons causing the error message. to find out which one follow the procedure in the troubleshooting extensions and themes article.

silkphoenix
silkphoenix
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If you have "ask toolbar" installed, uninstalled it. Most users have the same problem with this add-on.

Renshi
Renshi Question owner
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I do not have the "ask toolbar" installed.

However, the issue was fixed when I reinstalled/updated Firefox Personas manually.

Hopefully it won't arise again.