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Loop in Firefox

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Clicking on an internet link (CG22@groups.io) in an Outlook 2019 message causes a loop in Firefox that creates unlimited tabs. I have to use the Windows 10 task manager to close Firefox.

Clicking on an internet link (CG22@groups.io) in an Outlook 2019 message causes a loop in Firefox that creates unlimited tabs. I have to use the Windows 10 task manager to close Firefox.

Chosen solution

You get tabs opening endlessly if you choose Firefox to handle a file or protocol and you should never do this.


You can check the network.protocol-handler.external.mailto prefs on the about:config page. If network.protocol-handler.external.mailto prefs are user set (bold) then right-click and Reset them to the default value. You can also try to change the network.protocol-handler.warn-external.mailto pref to true.

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That is not a link. The @ makes it to be a mail address.

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Chosen Solution

You get tabs opening endlessly if you choose Firefox to handle a file or protocol and you should never do this.


You can check the network.protocol-handler.external.mailto prefs on the about:config page. If network.protocol-handler.external.mailto prefs are user set (bold) then right-click and Reset them to the default value. You can also try to change the network.protocol-handler.warn-external.mailto pref to true.

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Ok after refresh Firefox. Thank you. JLT