Change MobileFrontend and Minerva by analogy with the core and Vector changes which have been proposed or merged. When IP masking is enabled:
- The mobile editor should not warn users that edits will be attributed to their IP address. Language similar to the core edit warning should be used.
- In the mobile editor, preview as an anonymous user should acquire a username (TempUserCreator::acquireAndStashName) and show that username in signatures, instead of showing the IP address.
- In the mobile editor, saving as an anonymous user should create the temporary account (possibly reusing the name from the preview stage) and redirect through login.wikimedia.org in order to acquire CentralAuth cookies. Then (maybe) show a post-save notification as in core.