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Script slows browser

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  • Last reply by Aman Routh

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In multiple web sites (Facebook and PCH and a puzzle site and others) the system slows and I keep getting error messages that various scripts aren't working. My Flash file increases dramatically (anywhere to 100 Mb). If I click on stop the script the problem comes back in minutes and if I delete the Flash memory it works for a few minutes then slows again. I'll add the Firefox troubleshooting page if that helps.

This all started at the same time as Flash and Firefox updates (I have the latest version of everything).

In multiple web sites (Facebook and PCH and a puzzle site and others) the system slows and I keep getting error messages that various scripts aren't working. My Flash file increases dramatically (anywhere to 100 Mb). If I click on stop the script the problem comes back in minutes and if I delete the Flash memory it works for a few minutes then slows again. I'll add the Firefox troubleshooting page if that helps. This all started at the same time as Flash and Firefox updates (I have the latest version of everything).

All Replies (1)

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Have you tried restarting Firefox in safe mode.

You can do that by simply pressing and Holding on the SHIFT key and double clicking on the Firefox icon on your desktop.

See Diagnose Firefox issues using Troubleshoot Mode


Moreover, Your System Details List shows that you have a user.js file in the profile folder to initialize some prefs on each start of Firefox.

The user.js file is only present if you or other software has created it, so normally it wouldn't be there. you can check its content with a plain text editor if you didn't create this file yourself.

The user.js file is read each time you start Firefox and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session.

You can rename or delete the prefs.js file and possible numbered prefs-##.js and user.js files to reset all prefs to the default value.

You can use this button to go to the Firefox profile folder:

Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)

Note that the "Application Data" folder in XP/Win2K and the "AppData" folder in Windows Vista and Windows 7 and later versions are hidden folders.


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