FirebaseError: Function Query.startAfter() called with invalid data. Unsupported field value: a custom object

[nguyenthihuong0501]

I use paging to looad the data so in the form of scrolling data
�Here is the code

public async readWithPagination(t: { new(): T },lastData: any | null, orderBy: string = 'sort',directionStr: 'desc' | 'asc'='desc') {
let result: any | null = null
let startAfter = lastData
if ( startAfter == null) {
let first = this.firestoreApp.collection(this.dataPath).orderBy(orderBy,directionStr).limit(1);
let snapshot = await first.get();
startAfter = snapshot.docs[snapshot.docs.length - 1];
}
result = await this.firestoreApp.collection(this.dataPath).orderBy(orderBy,directionStr).startAfter(startAfter).limit(1).get();
return this.convertDocumentToModel(result, t);
}

[kevmoo]

The code here looks like Javascript. Is this a bug w/ the Dart package or the JS code?