Thanks for raising the concern.
The reason you are seeing this is when you create a custom field you have to provide a unique key
to it. This property is there for some time now and it was always a required
field. The recent change we made in this regard is that we are now validating it to have a non-empty value. The reason we had to validate is that it introduces an issue while rendering the custom fields on the property pane. If you are passing an undefined
or null
or empty
value for the key
prop then you will see this error.
/**
A UNIQUE key indicates the identity of this control.
The PropertyPane uses ReactJS to render its components. ReactJS uses keys to identify a component and if it should be re-rendered or not. This is a performance feature in ReactJS. Please read the following link to understand how to pick the value of the key.
@see https://facebook.github.io/react/docs/lists-and-keys.html#keys
*/
key: string;
So, the resolution for this would be that you have to pass in a non-empty value for that prop.
Please let me know if you need any more guidance in this regard.
Thanks for understanding,
Srikanth