/** A VisibilityGroup to manage the visibility of some of our controls.
* We fill it with the controls that are being managed, using the same names
* as those used with _mixer_strip_visibility in RCOptionEditor. Then
* this VisibilityGroup is configured by changes to the RC variable
/** A VisibilityGroup to manage the visibility of some of our controls.
* We fill it with the controls that are being managed, using the same names
* as those used with _mixer_strip_visibility in RCOptionEditor. Then
* this VisibilityGroup is configured by changes to the RC variable