A note on GUI docs
Most GUI tools frankly don't need docs at all. They're too simple. A combination of intuitive design and some in-app help is enough. These are tools no one would describe themselves as a "power user" of.
Other tools have more depth, and various levels of mastery. A veteran Microsoft Excel, Adobe Premiere, or Chrome Devtools user can do either one or more of the following relative to the average user:
- Achieve more with the same tools
- Achieve the same results faster
- Save time avoiding pitfalls and undesirable results
Ideally all GUI tools have the option of mastery. Make a Spotify playlist with SQL filters or schedule Zoom calls with keystrokes. But this shouldn't occupy valuable frontline UI space for the vast majority of people that would only be confused by the option. That's what the docs should be for.
Instead, GUI tools typically have docs/help pages like the 10-page manual that came with my flashlight. You have to wade through pages of obvious, already-inuititive stuff to get to any useful, unintuitive stuff.
Users of mainstream apps have different levels of intuition and experience, so the exhaustive docs for them makes sense. D2 Studio serves a niche of professional software engineers, further niched into ones that have no trouble picking up a new language. So these docs don't have to include things like how to click here then click there to create a diagram.
The goal of these docs is that every page shows you something that we feel is not as intuitive through just the UI as we'd like. There's no secret menu of things you can do, so it's all accessible through the app without the existence of the docs. It's just that a clean UI means only a limited amount of explanation can be included in the app.
In addition, remember there are separate docs for D2 (which I would recommend reading beforehand -- at least the "Getting started" section), and a manual for TALA, our layout engine (which is a much more optional read). So these docs will be short and focus only on parts of the IDE that can be described as not intuitive, but will aide you greatly to discover features that you will find useful in making beautiful diagrams.