Can't get 2.3.3 installed with snap to find help files

In installed with snap from the Ubuntu SW manager and it works great. Thanks for a useful program. Now I want local help files installed. Urk. No joy.
I’ve followed the instructions at https://manual.audacityteam.org/man/unzipping_the_manual.html but neither location works.
The preferences:interface option doesn’t give me a whole path for help files, just “local”. Where is that exactly?

I tried sudo unzip ~/Downloads/audacity-manual-2.3.3.zip -d /usr/share/audacity/help/ which puts the manual in
/usr/share/audacity/help/manual with icon and index.html located there. Audacity still tells me the manual is not installed.

How can I figure this out?
Thanks

Snap packages are sandboxed (isolated from the outside world), so it’s probably not possible to access the manual unless the manual has been built into the snap package.