In production rigs, such as those for Peach and Plumiferos, custom bone shapes are often simple wireframe shapes (formed with a single line). These are only visible when the armature's drawtype is Wire, which means that this drawtype must be used for the display of those bones. On the other hand, 'normal' bones must also be drawn as wireframes.
I've added a small toggle beside the field for the name of the object to use. This is marked 'W' (this is not great, but it'll have to do for now).
When activated, that bone's custom bone shape will always draw as a wireframe. As a result, the armature's drawtype doesn't have to be set to 'Wire' to see these bones.
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