Playing technique extension line disappears over grace notes.

I’ve encountered an issue in my project where, if I place a playing technique with extension line over grace notes and which happens to be in the first measure of the system, if I extend the line just after the last grace note, it disappears completely. The issue doesn’t occur if the line doesn’t extend up to the last note, if it goes past it or if the measure isn’t in the first bar of the system.
I attach the project with the problem. Try to extend the line with Alt+right arrow, the line will disappear. If you hit it again, it will reappear again. If you delete any bar after the System break, in order to make the bar not be in the beginning of the system, the issue does not occur.
dissapearing spiccatto.dorico.zip (816 KB)

Sorry for not acknowledging this post sooner. Just to say that I can confirm the behaviour and we’ll look into this when we can.

Thanks! Keep on with the good work!