mermaid SVG output does not appear correctly

Have been generating workflow graphs using mermaid (https://mermaidjs.github.io/) and mermaid-cli (https://github.com/mermaidjs/mermaid.cli). SVG generated from there is viewable in browsers, but appears as an empty window in Gapplin.

This issue appears in both QuickLook (native osx QL works) and in the application proper.