Failed to verify new iOS login from Web

It worked eventually, but got stuck on the web side, and then re-prompted to verify on the iOS side despite completing emoji verification. See rageshakes.

Start by reproducing the web-to-iOS login verification flow described in the issue, including emoji verification and the repeated iOS prompt. Trace where the web side becomes stuck and compare the verification state before and after completion. Done means a new iOS login completes verification without a web-side hang or another iOS prompt.

Written by the indexing model from the issue text.