- App sources can be seamlessly edited from within the app (though packaging
  up modifications to share with others currently has some seams; see below)

- Notes can contain hyperlinks in [[wikiwords]] to other notes. Hyperlinks
  can't contain spaces. Clicking on a hyperlink opens the target in a new
  column.
- A few other things. Explore the command menu and palette along the top.
Some videos to help visualize these bullets (albeit with outdated UI):
  * https://archive.org/details/akkartik-pensieve-2022-07-27 (4.5 minutes)
  * https://merveilles.town/@akkartik/108766067153506592 (30 seconds)