It is one of the great features that makes it my first choice for drawings.

I've used it for the png diagrams on a bit I wrote about the skip list ( https://shagie.net/2015/05/18/the-skip-list/ ) so that I could go back and be able to manipulate the drawing that its based on (import from - url - https://shagie.net/wp-content/uploads/2015/05/Untitled-Diagr... ) rather than the pixels in the image.

You can even export a SVG that embeds the drawio source. This is how I make diagrams for my projects: I can display them directly from my README, and after editing them in Draw.io's Visual Studio Code extension, I don't have to go through another export step.

I has become my go-to tool for many reasons.

- there is an electron version but also a web version which almost works as well which can be great in environments where downloading an electron app is hard.

- many enterprises with Confluence have a plugin in Confluence for embedding drawio.

- embedding the source in .png etc.

- support for UML shapes without forcing me to obey all the rules allowing for quick and dirty sketches.

- quick to use, decent usability.

- acceptable learning curve so I feel ok recommending it to others.

Just like Macromedia Fireworks in 1998!

That is indeed a killer feature.

One file that displays universally on all browsers or image-viewers while still also being the file that you can easily edit. I've also noticed it doesn't make the file that much bigger. (1-10KiB with some of my larger drawings)

Did not know that second part!