🧩 What’s causing this?
This problem was caused by attempting to define an additional flashing type at the bottom of the flashing line type list.
✅ Fix 1: Remove the offending line type
Go to System Preferences
Select Set Line Styles
Remove the offending line type
✅ Fix 2: Check Linestyles_V6.csv for an incorrect [END]
Also spotted where someone put an [END] at the bottom of the Linestyles_V6.csv file and that caused it to crash.

