Enable code navigation on the air-gapped instances

Sourcegraph code navigation is implemented on top of extensions. Code-intel extensions are enabled by default. Sourcegraph extensions are fetched from sourcegraph.com extensions registry, so to make use of them the Sourcegraph instance should have Internet access and properly configured extensions.remoteRegistry site config setting. Using a proxy to access the Sourcegraph extensions registry is not supported.

To make code navigation work on the air-gapped Sourcegraph instances code navigation extensions should be added to the instance's private extension registry following this guide.

Note: To get the list of the programming languages code navigation extensions run the following src CLI command against sourcegraph.com

src extensions list -query='sourcegraph/ category:"Programming languages"'

Languages specifications for which search-based code navigation is supported are listed here.