Geojson Layer via Url - how to update schema?

[ITSDevelopment]

I am adding a geojson layer/file to a map in ArcGIS Online via a url. The layer is at: https://adaptergis.cityoflewisville.com/gisfiles/ParcelsDashboard.json

After adding the layer to a map, I added an additional field to my geojson file. How do I get the map to see the new field I have added?  

I believe that the map saves the geojson file's schema somewhere on ArcGIS Online as an "operational layer" for my map.  

Does anyone know if the schema can be updated either via the UI or the REST API?

Thank you!

[ITSDevelopment · Accepted solution]

I figured it out!

Using the https://ago-assistant.esri.com/ page, I was able to use the experimental/beta feature to edit the /Data endpoint of my map. I added the new field in the "operational layers".

This will work but a more seamless and user-friendly option would be to have the map automatically refresh the schema of a layer brought in via a url (like a geojson file)