Title: Color Selection does not open when having selected components with different colors.
Environment: Windows 11 Home, StarUML v6.0.0 Pro
Actions Performed:
1. Create 2 classes in a class diagram.
2. Add different background color to them, each one separately.
3. Now select both classes, and try to add to both of them a different common color.
Expected Result:Color panel should open and selected color should be applied to all selected items.
Actual Result:The color panel does not open, thus no color can be applied.
Supplements:If the items have the same exact color then it works as it's expected. If the color is different it does not work.
This also happens in other diagrams like flowchart, BPMN etc. Thus it's probably a generic bug.
I think in previous version 5.1 it was working ok.
See also the image.