Dashboard: columns are being reset to default when repositioned using drag and drop

Overview:
In the New/Edit pane for a simple search, column options are being reset to default when repositioned using drag and drop.

Steps to Reproduce:

1. In the Dashboard app select "New" to open the New widget pane.
2. Add several columns.
3. Set each "Column" selection to something different.
4. Use the drag handles to reposition the columns.

Expected Results:
The options selected in step 3 are retained.

Actual Results:
The options are all reset to "Agreement name".

Additional Information:
See attached mp4

Dev task breakdown

This isn't happening in local builds, so is likely some dependency clash. Needs investigation along those lines.