I am able to add a new line at the end of a GA callsign by doing the following:
- Select a new country
- Type in something valid, followed by enter
- Click OK, then save
- Note that the callsign has a new line at the end. This messes up several views due to text clipping into each other
I can even add more than one new line, or add new lines before the custom section of the callsign. These produce an error code 12 when clicking ok but the callsign still saves in that instance.