Milestone stats / graph
Currently the trickiest part of using the Kanban workflow is that there is no visual indicator of the status of a milestone, and even inside of Gitlab the graph of percentage done is only effected by closed issues.
Ideally there should be something in Kanban, ideally within the milestone swimlane, that shows the overall status of the images and their states, something like the following:
Ideally the colours would be those assigned to the different labels used by Kanban, in the same order as the columns. Maybe with something to give the actual percentage on hover.