I think we should add `open-protocol-handler` to the permissions section in about:preferences#privacy. The dialog there could also have UI to disable the permission prompt for specific protocols. Managing double keyed permissions in the page info permission list seems to complex, so I wouldn't add it there.
Bug 1678994 Comment 5 Edit History
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I think we should add `open-protocol-handler` to the permissions section in about:preferences#privacy. The dialog there could also have UI to disable the permission prompt for specific protocols. Managing double keyed permissions in the page info permission list seems too complex, so I wouldn't add it there.