Ask HN: FOSS notes offline app with navigation tree, ideally cross platform?

What solutions do HN users use for note taking?

So far most of the notes app I see require accounts or are webapps that allow self-hosting. Offline locally run apps are designed for collaboration or development and not quite what I am looking for.

Ideally, I would like a locally run non-electron app that understands markdown files, can show a navigation pane based on markdown headings, and has tabs and allows saving sessions.

To meet that need I use texstudio, never compile, and just use headings, subheadings and subsubheadings so they show up in the navigation pane, but doing the same thing with markdown and an app based around doing so would be preferable.

Are there any good solutions for such a workflow?