Annotations in pdf files are stored in SQLite databases here:
Code:
/data/user/0/com.onyx.kreader/databases
Could you please check whether this file folder is empty.
What does "have just refreshed my boox max lumi library" mean?
Updating to firmware 3.1 (the database format changed with this version) or replacing pdf files?
Scribble information are connected in onyx database to pdf meta data. Have you changed them?
Please use the export icon in the scribble toolbar to embed scribble annotations into pdf file.