Scale in piano roll
Create midi file for scale/s and put them in ardour bundle / clip browser section
Then in editor list when left click on this midi file appears a menu contain this option
‘Use midi file as scale Reference’
No need develop each scale separately
in this case better than this patch
Just click on midi file of scale / chord / melody / arp … etc
then select this option ‘Use midi file as scale Reference’
Scale colored on piano roll (dark green represent scale keys / light green represent root key of scale)