Hi Pancakeater, What kind of site is opened after 2 seconds? Does it look like advertisement? It could be that your Firefox installation has been hijacked. Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of. You can try these free programs to scan for malware, which work with your existing antivirus software: * [http://www.microsoft.com/security/scanner/default.aspx Microsoft Safety Scanner] * [http://www.malwarebytes.org/products/malwarebytes_free/ MalwareBytes' Anti-Malware] * [http://support.kaspersky.com/faq/?qid=208283363 TDSSKiller - AntiRootkit Utility] [http://windows.microsoft.com/MSE Microsoft Security Essentials] is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one. Further information can be found in the [[Troubleshoot Firefox issues caused by malware]] article. Did this fix your problem? Please report back to us, and help others with the same issue.

This also might be caused by a plugin like Flash that is used in this tab that uses the plugin-container process. You can check for problems with current Flash plugin versions and try these: *disable protected mode in the Flash plugin (Flash 11.3+ on Windows Vista and later) *disable hardware acceleration in the Flash plugin *http://kb.mozillazine.org/Flash#Troubleshooting