Notify user of domain mismatch
Everyone can contribute. Help move this issue forward while earning points, leveling up and collecting rewards.
Description
When Gitlab is configured behind a reverse proxy it sometimes happens that information about the domain on which Gitlab runs is passed incorrectly. This causes various subsequent issues, e.g. with gravatars generated using the HTTP domain instead of the secure one, or the 2FA/U2F App-ID bound to the wrong scope (and thus failing in interesting ways).
Providing the user with a notification about this misconfiguration can help diagnose the issue faster or avoid unintended breaking of registered U2F tokens when the issue gets resolved "by accident".
Proposal
Include some JS on the web UI that checks that the actual domain and the domain that Gitlab thinks it is running on match. If they mismatch a notification is shown to notify of the issue. full domin mismatch sample.com vs. example.com MAY get a different message from http://example.com vs. https://example.com.
Links / references
Related to discussion https://twitter.com/BenBE1987/status/806473146383613952, resolved by https://twitter.com/BenBE1987/status/808464563087740928