Sending an event with a numeric property named 'length' causes data loss

[lourd]

I just stumbled upon this unfortunate bug after several weeks of data loss in my product.

If you send an event with a property named length with some numeric value, it will end up sending no properties at all with that event at all — including the $insert_id. This means that Mixpanel backend is unable to process the event, and the data will be lost.

The other Mixpanel SDKs (or at least the Unity SDK) handle this just fine. I'm assuming there's some weird JS quirk causing this bug.

[aamirv]

Yes, I encountered this, too. Thanks for flagging!