I have the tel: protocol's default handler set to Microsoft Your Phone, so I can place calls and send SMS from my computer. When I click a tel hyperlink in Firefox (e.g. tel:(555)555-5555), I get a FF prompt asking to Allow or Deny the website's ability to open this type of link, with an optional checkbox to remember this preference.

I would like to set a global default preference to always allow tel link handling by any website. However, I can't find any option in Settings (about:preferences) or about:config to make this happen.

In about:config, the preference permissions.default.camera controls the default behavior for webpage access to the camera, for example. A value of 0 is "Always Ask," and I think a value of 2 is "Always Deny," so I presume a value of 1 would be "Always Allow." I have tried creating new preferences named permissions.default.tel, permissions.default.telephone, and permissions.default.phone, but none of them have had any effect.

In fact, I can't even find a preference that stores the information about which sites I've granted permanent tel access to by using the "remember this decision" checkbox. Firefox has to store this data somewhere, so if I can even find that, maybe I can add "https://*.*" to the list.

So, how do I set the default preference to always allow handling of a specific protocol?

1 Answer 1


In order to automatically open a protocol like tel: with the default assigned handler application, without being asked for site-by-site permission, navigate to about:config and create a new boolean preference network.protocol-handler.external.tel. Set it to True. (To globally deny permission to a protocol instead, you would set it to False.)

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