I created the method which returns IMongoQueryable as result and the method is following:
GetCollection(GetCollectionName(collectionName), federatedDBKey).Find(query).As<T>();
The problem is this returns as IFindFluent. Before there were extension method AsQueryable which solved this, but now there is no that method anymore. I tried using IMongoCollectionExtensions.AsQueryable<T> and it works only with GetCollection but when I add this part for Find and As there were several errors. Any tip how to solve this?