I’ve actually never thought of this! 
In my Windows 11 machine, I had to add pap as a file type that can be indexed. After that, I got a hit when searching for a word inside of a .pap file with Windows Search. Here’s how:
- Go to Settings in your Windows.
- Search for “Indexing Options”, and open it.
- Choose “
Advanced”, and open the “File Types” tab. - Add pap as a new extension, and click “add”.
Depending on your indexing settings, it can take a while for this to apply
→ After adding the filetype, and choosing “Index Properties and File Contents”, the search should work.
Let me know how it goes! 
