1. After creating a custom field (in product module) and add it so it appears on the grid view (by ticking add/remove columns), it works well.
  2. Change the position of the custom field to be the 3rd column for instance
  3. Create a second custom field, make it visible in grid view by ticking add/remove columns
  4. Observe that the first custom field is now back to the very right of the grid view.