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I keep getting this error code window and it endlessly repeats DragDropUpload exception in track ReferenceError: nsDragAndDrop is not defined

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  • Last reply by cor-el

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I open firefox and a dropdown window appears with this message. DragDropUpload exception in track ReferenceError: nsDragAndDrop is not defined. I ca click on canceler OK. Clicking OK causes the window to close and immediately repeat. I can quit firefox.

I open firefox and a dropdown window appears with this message. DragDropUpload exception in track ReferenceError: nsDragAndDrop is not defined. I ca click on canceler OK. Clicking OK causes the window to close and immediately repeat. I can quit firefox.

Chosen solution

Is this a problem with an extension (FireFTP)?

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
  • Do NOT click the "Refresh Firefox" button on the Safe Mode start window
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Chosen Solution

Is this a problem with an extension (FireFTP)?

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
  • Do NOT click the "Refresh Firefox" button on the Safe Mode start window