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AlternateServices.txt - what does this file do?

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Just curious what the text file "alternateservices.txt" has for function. It is located in the Firefox user folder on Windows 10 systems.

Would be grateful for answers.

Just curious what the text file "alternateservices.txt" has for function. It is located in the Firefox user folder on Windows 10 systems. Would be grateful for answers.

Chosen solution

HTTP Alternative Services is a mechanism that allows servers to tell clients that the service they are accessing is available at another network location or over another protocol. This mapping can be stored in a file in the profile folder. This allows websites that do not support HTTPS to communicate in a secure way via port 443 (Opportunistic Encryption).


RFC 7838 - HTTP Alternative Services https://tools.ietf.org/html/rfc7838

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Chosen Solution

HTTP Alternative Services is a mechanism that allows servers to tell clients that the service they are accessing is available at another network location or over another protocol. This mapping can be stored in a file in the profile folder. This allows websites that do not support HTTPS to communicate in a secure way via port 443 (Opportunistic Encryption).


RFC 7838 - HTTP Alternative Services https://tools.ietf.org/html/rfc7838