Option to show only open or closed issues in Roadmap
In Roadmap page, it is difficult to find open issues when a version has hundreds of issues.
One good example is Roadmap page of www.redmine.org as of 2019-10-29. The target version 4.1.0 has more than 240 issues in the list, of which 6 are open. It is impossible for me to find open issues at a glance. In addition, the page is very long.
It can be improved if Roadmap page has checkboxes to show/shide open or closed issues in the sidebar.