title: Foundry-Workshop - Charts with multiple layers
body: <p>I would like to know what are the settings capabilities on workshop charts when implementing multiple layers.</p>
  <p>Here is an example of a chart with 2 layers (3 objects):
  <a href="https://i.stack.imgur.com/hZeJE.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/hZeJE.png" alt="enter image description here" /></a></p>
  <p>Among the global settings options, I would like to know:</p>
  <ul>
  <li>how to have only one legend per group, instead of one per layer?</li>
  <li>how to manage colors? Is it possible to change default?</li>
  <li>is there any way to display dotted lines for example?</li>
  </ul>
  <p>Thanks in advance</p>