With AutoHotKeys https://autohotkey.com/

(Create Button @ 22 in 70 down, 70 width 30 height, C Name )
Gui, Add, Button, x22 y70 w40 h30 , C

(Button function when clicked, send to Biab window "TBandWindow" (get name with WindowSpy.ahk))
ButtonC:
winactivate,ahk_class TBandWindow
Send C
Return


Gui, Add, Button, x22 y370 w90 h20 , Maj9

ButtonMaj9:
winactivate,ahk_class TBandWindow
Send Maj9
Return

so Biab will get a CMaj9

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