Separate Security Issue, please update your Flash 29.0 r0 Flash Player Version: 30.0.0.113 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only> HI, suggest you do this : *https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer *https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles As Firefox will want to do a Refresh due to the warning you are getting. Or it wants to close a script that is hanging. If this is a repeatable action only go to 1 website at a time to see which Firefox says is slowing things down. ”Webpage is slowing down your browser” This is the new way the browser tells you there is a problem with the script program(s). https://support.mozilla.org/en-US/kb/warning-unresponsive-script?cache=no You can try clearing your cache and your cookies : *https://support.mozilla.org/en-US/kb/how-clear-firefox-cache *https://support.mozilla.org/en-US/kb/delete-cookies-remove-info-websites-stored You can also do this : The other option is "Wait". I am pretty sure that your computer is not infected, but just to be sure, you can download, install and run https://www.malwarebytes.com/, and https://www.malwarebytes.com/adwcleaner/. Then, on your keyboard press the Windows key + R simultaneously. Then, type Cleanmgr. Then, press check the boxes that need to be then Enter. Then, press OK. Then, wait for the clean-up to finish. Then, restart your computer. The above is Window's Disk Cleanup and should be run weekly. Please let us know if this solved your issue or if need further assistance.

”Webpage is slowing down your browser” This is the new way the browser tells you there is a problem with the script program(s). https://support.mozilla.org/en-US/kb/warning-unresponsive-script?cache=no