Changing the default theme for plantuml

[Inithron]

Hi,

When I change inside a plantuml diagram the theme with !theme spacelab, I can see it in the internal and external preview. But how can I change the the default theme for all plantuml diagrams? I tried to add :plantuml-theme: spacelab into the .asciidoctorconfig file and into the asciidoc file who is importing the diagram but it is not working. Eclipse always displays the diagrams with its own default theme. Only when I create the HTML and PDF documents via the Gradle asciidoctor task, I can see the 'spacelab' theme in the diagrams.