Photoshop extended not required.
The documentation states:
Convert To Timeline Animation (Photoshop Extended)
Converts a frame animation to timeline animation using keyframes to animate layer
But it’s certainly fine with me if it’s available in Standard.
Adobe documentation is in poor shape. Much work is needed in the documentation to make it up to date. Adobe replaced Photoshop Animation Palette in CS6 with the Timeline Palette and added basic video support into standard Photoshop CS6
I do have extended, but it wasn't let me choose because I was using the 64-bit version of Photoshop CS6. Apparently, it only has frame animation in the 64-bit version. It works fine in 32-bit.
The screen capture you posted above does not look like CS6 extended for there are missing menu like 3D etc. I have no problem with frame animation in CS6 Standard 64bit and 32bit???? I would think the same would be true with CS6 extended.