A React migration lesson I wish I’d turned into a check earlier:
Edit a character in the middle of a long text field. Does the caret stay where the user expects?
During a recent React 19 migration, we encountered a regression where it jumped to the end. That doesn’t establish a React framework bug—but it exposed a behavior worth checking explicitly.
I’m building AEG to explore how lessons like this can become reusable checks for developers and coding agents.
Here’s the early React 19 Migration Acceptance Pack.
What’s one migration check you added only after something broke?
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