fix: warn when Partial with append/prepend mode is missing key prop#3738
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Without a key, Preact cannot correctly reconcile prepended/appended children, leading to subtle rendering bugs. This adds a console.warn during server-side rendering so developers get immediate feedback. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Update examples to include key props and upgrade the info box to a warning explaining why keys are required and that Fresh now warns when they're missing. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
console.warnduring SSR when a<Partial>usesmode="append"ormode="prepend"without akeypropmode="replace"(default) since keys aren't required thereTest plan
mode="append"without keymode="prepend"without key🤖 Generated with Claude Code