I think it's all tied in together with other disappearing or moving chords when selecting from the left or selecting from the right and ctrl+c

https://www.pgmusic.com/forums/ubbthreads.php?ubb=showflat&Number=674799

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BiabVST-The-Disappearing-Chord.gif (168.88 KB, 84 downloads)
BiabVST-Chord-Copy2.gif (113.97 KB, 84 downloads)