Please mention "lock" button in documentation

Hi, doc enhancement request: please mention the functionality of the “lock” button somewhere in the documentation, all that’s needed is a little section somewhere. (unless I missed it, apologies if so). Locking the current musical composition allows the user to preview some musical ideas without the notes being recorded (which is very distracting).

This is a powerful feature which enables the user to lay down some chords and rhythms and then jam against them for a while to develop a musical idea. The feature exists but does not seem to be surfaced in the documentation very effectively (again, unless I missed it)

I’m following up on the suggestion from @magicalmbeth and reply by @Josh1billion, thanks both! Also an earlier request by @alfordtp, thanks as well