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what does this mean when I try to open a new window "Exc in ev handl: TypeError: brw is undefined

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  • 6 have this problem
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  • Last reply by cor-el

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The above message pops up when I click on new window, once I click OK the message goes and a blank new window does appear. It has also just happened when I was in BBC language site and tried to open a link, the message appeared but once I clicked OK the message went and the link did open. It does not happen when I open a new tab. This has only just started to happen over the last few days.

The above message pops up when I click on new window, once I click OK the message goes and a blank new window does appear. It has also just happened when I was in BBC language site and tried to open a link, the message appeared but once I clicked OK the message went and the link did open. It does not happen when I open a new tab. This has only just started to happen over the last few days.

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This issue can be caused by the McAfee Site Advisor extension


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).