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How can I stop a script error on starting Firefox?

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70% of the time I get the error message when loading firefox. "A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete. Script: file:///C:/Program%20Files/Mozilla%20Firefox/components/nsBlocklistService.js:648" Firefox takes a long time to load and I have to stop the script before it will load. I would like to solve the problem

70% of the time I get the error message when loading firefox. "A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete. Script: file:///C:/Program%20Files/Mozilla%20Firefox/components/nsBlocklistService.js:648" Firefox takes a long time to load and I have to stop the script before it will load. I would like to solve the problem

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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of your add-ons is causing your problem (switch to the DEFAULT theme: Tools > Add-ons > Themes).

  • Don't make any changes on the Safe mode start window.

See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems and Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

If it does work in Safe-mode then disable all your extensions and then try to find which is causing it by enabling one at a time until the problem reappears.

  • Use "Disable all add-ons" on the Safe mode start window to disable all extensions.
  • Close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")
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Cor-el-

Thanks for the instructions. When I opened my Firefox in safe mode, two of the add-ons had exclamation points and notes that the toolbars were not compatible with the browser. I uninstalled them- will see if it fixed the problem.