This is a reference entry from React error codes. A full explanation with fixes has not been written yet.
flushSync was called on the server. This is likely caused by a function being called during render or in module scope that was intended to be called from an effect or event handler. Update your to not call flushSync no the server.
%s is filled in by React at runtime.
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- Minified React error
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- error
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Source: React error codes. Data fetched 2026-09-25T01:43:12.929Z.