Bravo Patrick.
I went ahead and tested the OMEMO IM app “Conversations” and it works flawlessly.
Please add to documentation:
To share files between Whonix and Anbox apps without complicated mounting instructions run
lxsudo thunar
Browse to:
/var/lib/anbox/rootfs/data/media/0/
Files dropped in the Dowload directory are readily visible to apps within Anbox - useful for sending receiving files from Conversations.