Great concept. Had high hopes and liked it at first but got tiresome and went back to Inkscape which is a much more mature but heavyweight and complex product for my limited needs and LibreOffice Draw is much too basic. Downsides - It's 2023 and I'm editing a text config file for preferences and styles. Default start up asks if you want a previous file then dumps you in a file window at the home folder (change showStartScreen to "false" in the config file, then use recent files) - a list of recent files would be good instead of the home folder. Though multiple glue positions are good, connector lines can be awkward to place accurately without accidentally generating more nodes. Extra nodes can appear at the end of lines and be difficult to delete to the point where they're just easier to "hide". No format painter. Weird defaults that seem to change unexpectedly - I kept getting arrow heads back when I wanted plain lines No selectable connector with plain ends? Odd glitches and crashes. Layers dialog doesn't rememeber size settings and can only use a corner handle to resize No easy way to view all objects present in one layer except turning all the other layers off. No seperate node tool. No use of the mousewheel on value boxes? This would be useful for line thickness, maybe colour for quick selection? Few more I can't remember. Upsides - Lots of content. Attractive but not entirely intuitive interface. Fairly clean export to SVG means going back to Inkscape isn't too painful. I'll definitely come back and try it again in a year or two.
Don't use draw.io as flatpak installation on Linux mate 21.2...it installs and works but u can't save or export the project, there is just a terrible workaround to save/edit the diagram and save it as text or xml. Later Importing is complicated by copy XML text as "edit diagram". Installed DEB from github works (https://github.com/jgraph/drawio-desktop/releases/tag/v22.0.3). The Application it self is the best one i got under my fingers for diagrams.
The application is running in some minimalistic browser window(webUI) / missing DE window buttons. All templates and stuff rely heavily on web service, offline it's minimalistic (you might as wel just use this tool from within your own browser / visit www.draw.io and safe your system a ~250MB flatpack)