diff --git a/support/doc/plugins/guide.md b/support/doc/plugins/guide.md
index 81999bf32..17c681afd 100644
--- a/support/doc/plugins/guide.md
+++ b/support/doc/plugins/guide.md
@@ -633,7 +633,7 @@ async function register ({ registerSettingsScript }) {
 
 PeerTube provides some HTML id so plugins can easily insert their own element:
 
-```
+```js
 async function register (...) {
   const elem = document.createElement('div')
   elem.className = 'hello-world-h4'