Hi cellicello
It appears that you are using natural harmonics in the violin, which can be shown using the ‘harmonics’ property when the note is selected and choosing the correct partial number.
Some of these also exist in your double bass part, whilst others are appearing as red because those are NOT harmonics, and rather just open strings. The first harmonic partial exist one octave above these notes (the double bass is a octave-transposing instrument).
Hope this helps!