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When opening Firefox, a box appears as follows: Javascript Application Exc in ev handl: TypefaceError: brw is undefined When the OK button is clicked, Firefox opens. Any ideas as to how to eliminate?

ramonwal
ramonwal
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When opening Firefox, a box appears as follows:

Javascript Application

Exc in ev handl: TypefaceError: brw is undefined


When the OK button is clicked, Firefox opens.

When opening Firefox, a box appears as follows: Javascript Application Exc in ev handl: TypefaceError: brw is undefined When the OK button is clicked, Firefox opens.

All Replies (2)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).

David McRitchie
David McRitchie
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Disable "McAfee Site Advisor" extension which was just updated to 3.4.0, which probably took it out of the addons block list.

  • "Ctrl+Shift+A" > find McAfee Site Advisor and use "Disable", and then restart Firefox.
  • Do a Google Search no problem
  • It seems that if you re-enable Site Advisor again, and restart Firefox you are okay. At least you know where to look if you get the error again or Google searches slow down.