Is there an open source option to Obsidian? This is the type of thing I wouldn’t want reading or tracking my inner thoughts. Preferably something that isn’t using a limited format like Markdown.
I don't know what kind of formatting you're looking for, but most of the apps I'm familiar with are markdown or just plain text. I use Vimwiki in markdown for my notes, but it can also be exported to HTML, which I don't use often.