You deploy an API change on Tuesday. On Wednesday you get errors from clients sending the old request shape. The frontend was deployed at the same time. What is happening, and whose problem is it?
Answer it out loud before you open anything. The value of the flags below is in comparing them to what you actually said.
The situation behind the question
An internal tool people keep open in a background tab for days. The API change renamed a field and dropped the old one. Error rates are low, persistent, and concentrated in a handful of users.
What it is really testing
Whether the candidate understands that the deployed frontend and the running frontend are different things. A candidate who assumes "we deployed, so everyone has the new code" has never operated a long-lived client.