Add a Legend to the Gantt Chart

Adding a legend to the Gantt Chart would help people viewing the chart to understand what the color of each bar means, especially if they are seeing it for the the first time. Currently if you make a custom roadmap and put it in a presentation a legend will automatically appear in that slide of your presentation, I would like the to see a legend also automatically appear if you put a Gantt Chart in a presentation. I would also like the option to have a legend when you are in the Gantt Chart for a certain workspace. Basically a legend should be present for the Gantt Chart whether it's in a presentation or not.