In sequence diagrams it is possible to change the color of objects, but not for messages. Reproducible: Always Steps to Reproduce: 1. start umbrello 2. add a sequence diagram 3. add two objects and a message between them Actual Results: There is no property dialog or context menu for changing the message line color. Expected Results: There should be a property dialog or context menu entry for changing the message line color.
Thank you for the bug report. As this report hasn't seen any changes in 5 years or more, we ask if you can please confirm that the issue still persists. If this bug is no longer persisting or relevant please change the status to resolved.