Add the ability to configure a proxy for WAC to Install and Update Extensions
When deploying WAC on a Windows Server as the ‘Windows Admin Center’ Service you cannot access Internet Feeds for Extensions (e.g. https://aka.ms/sme-extension-feed) via a proxy server if the Server does not have direct access to the Internet. This means the user experience is diminished as new Extensions cannot downloaded via the Extensions section in WAC and / or existing extensions cannot be updated via the Extensions section.
It can be achieved by setting a proxy for the Network Service account that the WAC Service runs under, but that's not ideal.
Suggest adding the option to configure a proxy the ‘Internet Access’ section under settings. Users would need to be able to specify the proxy server address, port, and any credentials if authentication is used (but have the option to just anonymous access with no credentials)