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[11:04:52] <rightnow> Hello! I have a aggreated query with several $lookups. I have a problem with a nested lookup. If i have collection vehicles and do a $lookup to engine, engine will be null if no join is found. This is fine! But if i also add a lookup to $engine.manufacturer, then engine will be an empty object instead. Is there any way i can get it to be null like in the first example?