I can’t give you nearly as much detail as some people can this topic but I can tell you that the basic concept is that the demo version no longer stores its information in a series of markdown files. Instead it stores everything in an internal database.
Where that databases or even if it’s accessible to us I’m afraid I can’t say. In their defence that website was never really designed for regular use so much as testing. I think we’ve begun to use it as a web app even though that wasn’t their original intention.
There’s been quite a bit of discussion about how to synchronize that database without using the paid for synchronization service. But perhaps synchronisation isn’t really what you’re after.
You should be able to export the entire graph if that’s of any use to you?
As far as I can tell, it must be using local storage in the browser (or similar). My main concern is data loss - if an update or security policy is pushed out that clears local storage, I lose everything.
I could periodically export, but that becomes a whole hassle that I don’t need to worry about right now.
I tested the latest nightly build and features are available according to the chart posted by @danzu, for example Zotero is available in MD mode but missing in DB.
However, Presentation mode seems to be missing from MD mode even though the chart lists it as supported. The “View as slides” option is simply not there. Searching through the code base on GitHub gives no results to reveal.js or slides either…