I really like DrawIo, and really hate it often, too. So much potential, but the learning curve is so steep.
After years of trying, I still can't change the foreground color of PNG icons, and if I cannot do that, no one ever seems to say so directly. But I assume they must be changeable because what good are they if they can't be customized?
Many great icons have awful colors, and all I can ever set is backgrounds and borders. Is there any way (short of editing a copy of the original PNG), to replace the foreground object color? I just can't believe all the developers using this product are using the random icon colors supplied with the PNGs that come with the app. What am I doing wrong (if anything)?
