When going to a project's settings, scroll down a lot, I'll eventually come to section "Roadmap", which contains three fields: "Milestone", "Date (optional)" and something with checkboxes. Please give a name to this last table's column so that we users know what it does.
Metadata Update from @pingou: - Issue tagged with: bug, easyfix
Metadata Update from @pingou: - Issue assigned to pingou
Commit 47360841 fixes this issue