Worth a mention: there are quite a few open source note-taking apps, alternatives to OneNote/Evernote. I use Joplin, but there are more here https://linuxstans.com/best-note-taking-apps-for-linux/
I'm trying to switch to fully open source apps, and ditching OneNote for Joplin was a great move.
Wow, that's a neat trick! I've never thought about using grep this way. Thank you for the great tutorial