Field order is not preserved at REST for referenced map services published from ArcGIS Pro.

Workaround

The workaround is to manually change the field order in a layer file to get the field order to show up correctly in the web map pop-ups.

1. Right-click a layer and select 'Sharing' or 'Save As Layer File'.

2. Open the exported LYRX file in a text editor.

3. Search "fields" : [

4. In the lines below, rearrange the field order. Make sure the last item does not contain a comma. For example:

      "fields" : [

       "device_type",

       "circuit_id",

       "owner_name",

       "date_installed",

       "esri_default_style"

      ]

5. Save the LYRX file.

6. For the same layer exported, go to 'Symbology' and select 'Import symbology'.

7. Browse to the LYRX file and select it.

8. The fields now reflect the order set in the LYRX file.

Follow the same steps for any future edits to field order.

Steps to Reproduce