I thought I remembered making a graphic for that.
Maybe if you ctrl click the chord when it has a shot hold etc..
it could bring up the track option and mirror it also in F5 like you show.
Also have a select all/none check box.
This will prevent the cramming.
Maybe you could have the b,d,g,s,p in that also ?
So it's backward compatible let it read C...b,d
into the check boxes already checked to be exempt and just display C...
Maybe it can be another color if there are exempt tracks ?
Or C...x

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