13.59Improvising over extensions

If chord is:

Cmaj9

you don't suddenly need a mysterious new scale.

The 9th D is already in C major.

Likewise:

Dm11 contains notes from C major.

G13 contains E, also from C major.

So:

Dm11 → G13 → Cmaj9

can still fundamentally use C-major material.

Again:

chord tones/extensions tell you what to emphasize.