I meant 40/50K items/documents in a single collection is causing problems with Firestore but it might not be the case anymore I didn’t use Firestore with wix-adapter for a long time.
And I didn’t understand what you mean by how to make a collection in a collection in a collection
i meant not having a flat structure and having a bunch of subcollections. Im new so i dont know the terminology 
And im just very curious what problems have you noticed. Because i will probably break the 50k barier in few months and im curious what will happen
This is amazing. Thank you for taking the time to create this.