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Wannan tattunawa ta zama daɗaɗɗiya. Yi sabuwar tambaya idan ka na bukatar taimako.
Ajiyayyu

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

Renshi

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)

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.

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

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.