Creating/saving a shape key from moving a bone (Rig) How can I create a shape key by moving the mesh's bone?

The bone I have selected will move the mouth mesh.

I moved it to the desired location.

And now I want to save this changed mesh as a shape key, so the slider will activate it and change it back to normal when the value is 0.


How can I save this final mesh as a shape key? The last picture will be the at the value of 1, and the first picture will be at the value of 0. Can I do this, without toggling Edit Mode, to create the shape key?

EDIT: Unless there's a way to save this pose (edited) in edit mode, I'll try to find another way to create this shape key.
Select your mesh, go to the properties window, modifiers tab, in the armature modifier you'll find a button named "apply as shape key" wich does exactly what you're asking for.