difference in notation between different instruments

I noticed a difference how D3 notates the rhythm of these two (equal) parts in an open style section (see attached project). One is for triangle, the other for suspended cymbal. I now faked it (in my own score) by replacing the cymbal with a triangle and changing the names, but I’d like to understand why it is different and if it is a setting, bug or something that hasn’t been implemented just yet.

duration problem.dorico.zip (440 KB)

You’ve overridden your default 8-times-whole-note Notehead. I don’t know why, but it’s easy to reset it.

ahhh thanks!
I don’t know either why I’ve done that…