title: PlantUML export of coloured legend to SVG fails
body: <p>I've followed the solution proposed <a href="https://stackoverflow.com/questions/30999290/how-to-generate-a-legend-with-colors-in-plantuml?rq=1">here</a> successfully, but when trying to export the legend to SVG, the only thin visible is the last encoded color. Am I missing a closing instruction to avoid this?</p>
  
  <p>Here you have a simplified example, try to export it to SVG and you will have a black square as a result. Export as PNG works fine.</p>
  
  <pre><code>@startuml
  
  legend   
  |= |= Colours | 
  |&lt;back:#F59175&gt;   &lt;/back&gt;| Pink | 
  |&lt;back:#FEFECE&gt;   &lt;/back&gt;| Yellow |
  |&lt;back:#000000&gt;   &lt;/back&gt;| Black | 
  
  endlegend
  
  @enduml 
  </code></pre>
  
  <p>Solution to the problem (thanks to the comment of <a href="https://stackoverflow.com/users/1309509/geekboy">GeekBoy</a> ):</p>
  
  <pre><code>@startuml
  
  legend   
  |=   |= Colours | 
  |&lt;#F59175&gt;| Pink | 
  |&lt;#FEFECE&gt;| Yellow |
  |&lt;#000000&gt;| Black | 
  
  endlegend
  
  @enduml 
  </code></pre>
  
  <p>NB. dimension of the first column is defined by the first cell |=  |.</p>