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Only allow single instance of firefox (one window only)

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  • 1 has this problem
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  • Last reply by Shadow110

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How can I force firefox to only run a single instance (window). If firefox is already running, and I try to run another instance, it should instead switch to the already running instance?

I'm on Windows 10, but that should probably not make a difference.

How can I force firefox to only run a single instance (window). If firefox is already running, and I try to run another instance, it should instead switch to the already running instance? I'm on Windows 10, but that should probably not make a difference.

All Replies (4)

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Firefox should not be opening New Windows unless you tell it to. Or are meaning tabs ? As there are Extensions that can be used to limit the number of tabs that can be opened. https://addons.mozilla.org/firefox/extensions/

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Hmm, what do you mean by instance?

Normally if you were to use your Firefox desktop shortcut when Firefox is already running, Firefox would open a new tab or new window in the same instance of Firefox -- meaning it is in the same session and the two tabs or windows will share history, cookies, etc.

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If firefox is already running, and I click its icon in the startmenu, or on the desktop, I want it to focus on the already open instance, not open a new window, as it currently does.

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Unfortunately that is not what the icon is for at this time. Have you checked out what happens when you right click it when it is running ?