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Click the "+" button to create a new conversion action.
Choose "Import" as the conversion source.
Select "Google Analytics (GA4) properties and Firebase".
Choose "Web" because you're tracking web-based purchase events.
You'll see a list of GA4 events marked as conversions. Select the "purchase" event, and any other events you want to track.
Click "Import and continue".
Review the details and click "Done".
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