Right click on the trend line.
You have now a new option Alarm.
The Alarm will work only on Extended Trend Lines and only on the real
time or last bar.
The 3 possibilities with the alarms are.
1. Set the alarm to none.
2. Set that will go off on a bar that on the close cross the trend line.
3. Set that will go off on a bar that at any time cross the trend line.
After the alarm goes off it will be set to NONE automatically