diff --git a/src/public/app/widgets/type_widgets/ckeditor/syntax_highlight.js b/src/public/app/widgets/type_widgets/ckeditor/syntax_highlight.js
index 396f2bea0..6d858d910 100644
--- a/src/public/app/widgets/type_widgets/ckeditor/syntax_highlight.js
+++ b/src/public/app/widgets/type_widgets/ckeditor/syntax_highlight.js
@@ -3,6 +3,8 @@ export function initSyntaxHighlighting(editor) {
     initTextEditor(editor);
 }
 
+const HIGHLIGHT_MAX_BLOCK_COUNT = 500;
+
 const tag = "SyntaxHighlightWidget";
 const debugLevels = ["error", "warn", "info", "log", "debug"];
 const debugLevel = "debug";
@@ -162,6 +164,11 @@ function highlightCodeBlock(codeBlock, writer) {
         log("not highlighting plaintext codeblock");
         return;
     }
+
+    // Don't highlight if the code is too big, as the typing performance will be highly degraded.
+    if (codeBlock.childCount >= HIGHLIGHT_MAX_BLOCK_COUNT) {
+        return;
+    }
         
     // highlight.js needs the full text without HTML tags, eg for the
     // text