diff --git a/docs/entityRelationshipDiagram.md b/docs/entityRelationshipDiagram.md
index 53a5c0ab3..1b8206c16 100644
--- a/docs/entityRelationshipDiagram.md
+++ b/docs/entityRelationshipDiagram.md
@@ -75,7 +75,7 @@ When including attributes on ER diagrams, you must decide whether to include for
 
 Mermaid syntax for ER diagrams is compatible with PlantUML, with an extension to label the relationship.  Each statement consists of the following parts:
 
-```markdown
+```
     <first-entity> [<relationship> <second-entity> : <relationship-label>]
 ```
 
@@ -88,7 +88,7 @@ Where:
 
 For example:
 
-```markdown
+```
     PROPERTY ||--|{ ROOM : contains
 ```
 
diff --git a/docs/index.html b/docs/index.html
index 00fb06fa7..3589afaca 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -46,8 +46,9 @@
     function colorizeEverything(html) {
       initEditor(monaco)
       return new Promise((resolve, reject) => {
+        monaco.editor.setTheme('mermaid')
         var parsed = parser.parseFromString(html, 'text/html').body
-        Promise.all([...parsed.querySelectorAll('pre[id*="code"]')].map(codeBlock => monaco.editor.colorize(codeBlock.innerText, 'mermaid', { theme: 'mermaid' }))).then(result => {
+        Promise.all([...parsed.querySelectorAll('pre[id*="code"]')].map(codeBlock => monaco.editor.colorize(codeBlock.innerText, 'mermaid'))).then(result => {
           parsed.querySelectorAll('pre[id*="code"]').forEach((codeBlock, index) => codeBlock.innerHTML = result[index])
           resolve(parsed.innerHTML)
         })