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Why does Firefox set network.protocol-handler.expose.(protocol) to "true" on every start?

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  • Last reply by cor-el

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I want to make FF open "file://"-links with the Windows Explorer. It works if I set "network.protocol-handler.expose.file" to false and "network.protocol-handler.external.file" to true. But "network.protocol-handler.expose.file" is missing in about:config after a restart. So i've set it in my user.js. Now I can see the variable but its always set to true no matter what stands in my user.js. Why is FF overriding my config?

I want to make FF open "file://"-links with the Windows Explorer. It works if I set "network.protocol-handler.expose.file" to false and "network.protocol-handler.external.file" to true. But "network.protocol-handler.expose.file" is missing in about:config after a restart. So i've set it in my user.js. Now I can see the variable but its always set to true no matter what stands in my user.js. Why is FF overriding my config?

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Chosen Solution

Try Locking preferences .


thank you

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That should be OK.

Firefox should store the protocol settings in the mimeTypes.rdf file.