I've locked my Document Stencil as Read-only. How can I make is Read-write?

[lovehate]

I know it's my doing, but I can't figure it out.  Document Stencil is usually read/write. You can drag shapes in there and edit them. But, after autoloading 3 custom stencils, my Document Stencil is locked for editing... every time.  I have no idea how to overcome this.  I might have coded it that way, but I cannot recall.
Thanks very much for your suggestions.

[Surrogate]

You want unprotect document stencil, what version visio?

[lovehate]

I'm using Visio 2013. Yes, I want to unlock the Document Stencil.

[Surrogate]

This command not in any ribbon!
You can add it to custom access toolbar or to  created custom ribbon
File -> Options -> Customize ribbon

[lovehate]

That's it! Thank you very much.  Getting old and forgetful.