when closing Firefox (v:3.6.13), using the red "close" button, the firefox.exe process remaines at top of the "Windows Task Manager" window and continues to use the majority of CPU time.
After an attempt to close the Mozilla Firefox page, on every occasion, the firefox.exe process is found at the top of the list when ordering the listed 'processes' by CPU time... even though the web page is gone. If an attempt is made to restart Mozilla, the system declares that the current Mozilla process should be closed.
If the firefox.exe process is explicitly closed in the Task Manager, only then can Firefox be restarted.
ప్రత్యుత్తరాలన్నీ (1)
Does that also happen if you use File > Exit Firefox?
See also "Hang at exit":