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There are times when the firefox responds reluctantly. And it is not only when i have opened many tabs. But there are cases when i have opened as many as 20 tabs and firefox is working fine and there are chances when i have opened just 5-6 tabs and firefox behaves lazy.
So, i guess it do not depend on number of tabs and there must be any specific tab which causes the problem.
Isn't there a way to find that tab out and close only that instead of closing complete firefox? Is there any addon for that, or any script?