Extensions not showing

I have Cubase 11 pro. The manual says Extensions should be in the audio menu, or if you right click on an audio event or if you right click the info line. It does not appear in any of these places. Any idea why I can’t see it? I’d like to use Spectral layers one.
Thanks for any help.

If you do not see the Extension in the drop down or info line, is it possible you are running a smaller version of Cubase and not Cubase pro?

Did you download SpectraLayers One?

Ah, I’ve just seen that I haven’t downloaded Spectral layers one under the cubase tab. Now its working fine thanks for you help!