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After a windows update, I now get "Error: 'alert' called on an object that does not implement interface Window" on every page. Is there a fix?

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  • Last reply by philipp

MaxH
MaxH

Wndows performed automatic updates last night. Now almost every page on every website generates several popups warning me that "Error: 'alert' called on an object that does not implement interface Window". Is there a fix?

Wndows performed automatic updates last night. Now almost every page on every website generates several popups warning me that "Error: 'alert' called on an object that does not implement interface Window". Is there a fix?

Chosen solution

hello, can you try to replicate this behaviour when you launch firefox in safe mode once? if not, maybe an addon is interfering here...

Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

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philipp
philipp
  • Moderator

Chosen Solution

hello, can you try to replicate this behaviour when you launch firefox in safe mode once? if not, maybe an addon is interfering here...

Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

MaxH
MaxH Question owner

Your suggestion worked... so I disabled the extensions one by one until the issue cleared; then I re-enabled all but the apparent offender -- narrowed it down. The culprit is the Kaspersky add-on. It was triggering the error when my mouse crossed over certain active elements, making the popup appear to be somewhat random. Hopefully, they'll get a fix out soon.

Thanks for the help, Philipp. I should have figured this out on my own, but it's been one of those days ;)

Modified by MaxH

MaxH
MaxH Question owner

and sorry for misspelling your name, Philipp.

philipp
philipp
  • Moderator

no worries, glad you could get it sorted...