[blocked] Speed up ArrayInput #10926
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Problem
The way useApplyDefaultValues and ArrayInput subscribe to the form context to check for dirty or error state force a full rerendering of all fields in a field array on each change. This is very harmful for performance.
Solution
react-hook-form v7.62.0 introduces a way to subscribe to form changes without triggering a rerender. We can therefore manage the dirty and error states by hand to avoid the rerender.
How to test
Open the console, change the value of one field. Only this field should rerender
Open the React profiler, update one value in the array input, check out the output: no rendering should rerender all fields.