hexo/node_modules/hexo-theme-fluid/layout/_partials/plugins/mermaid.ejs

<script>
  Fluid.utils.createScript('<%= url_join(theme.static_prefix.mermaid, 'mermaid.min.js') %>', function() {
    mermaid.initialize(<%- JSON.stringify(theme.post.mermaid.options || {}) %>);

    Fluid.utils.listenDOMLoaded(function() {
      Fluid.events.registerRefreshCallback(function() {
        if ('mermaid' in window) {
          mermaid.init();
        }
      });
    });
  });
</script>