Unable to save edits in related tables in ArcGIS Field Maps mobile when web map is only opened or worked in Map Viewer.

Workaround

Classic Map Viewer workflow.

1.     Publish hosted feature layer from ArcGIS Pro to ArcGIS Online. Feature layer includes point layer and related table using Global ID and GUID.

2.     Open hosted feature layer in ArcGIS Online using Map Viewer Classic and create a new web map.

3.     Update settings for the feature layer to enable editing and update settings in the web map to allow use in ArcGIS Field Maps mobile app.

4.     Open the web map in ArcGIS Field Maps and update the forms to include two test questions.

5.     Open the web map in ArcGIS Field Maps on a mobile device. Add data to the related table for any point.

6.     Open the same related table and edit data.

7.     Data edit is applied as expected.

Steps to Reproduce