diff --git a/Developer.md b/Developer.md
index bd1ff80..d3035a4 100644
--- a/Developer.md
+++ b/Developer.md
@@ -36,8 +36,8 @@ This article is written for internal use, just for convenience.
 - Utility : Some data-process helper.
 - Youtube : Any video upload in youtube.
 
-## Prefix
-- [Close duplicated] : Old issue, not implemented or fixed in the current milestone.
+## Badge
+- [outdated] : Old issue, not implemented or fixed in the current milestone.
 
 ## Example link
 
diff --git a/layouts/changelog/single.html b/layouts/changelog/single.html
index a9d9378..9ce4c7c 100644
--- a/layouts/changelog/single.html
+++ b/layouts/changelog/single.html
@@ -110,4 +110,5 @@ <h3 class="single__subtitle">{{ .Params.subtitle }}</h3>
 </script>
 {{ partial "script/single-script" . }}
 {{ partial "script/github-mention-link" . }}
+{{ partial "script/badge" . }}
 {{ end }}
diff --git a/layouts/partials/script/badge.html b/layouts/partials/script/badge.html
new file mode 100644
index 0000000..adfaef3
--- /dev/null
+++ b/layouts/partials/script/badge.html
@@ -0,0 +1,29 @@
+<script> 
+    // replace [text] to badge style.
+    function replaceBadge(innerHtml, mappings) {
+        return innerHtml.replace(/\[(.*?)\]/, (match, p1) => {
+            const mapping = mappings[p1];
+            if(!mapping) {
+                return match;
+            }
+
+            const color = mappings[p1].color;
+            const style = 'background-color: ' + color + '; color: white; padding: 4px 8px; text-align: center; border-radius: 5px; font-family: Arial, Helvetica, sans-serif;'
+            const replaceWith = '<span style="' + style + '">' + p1 + '</span>'
+
+            return replaceWith;
+        });
+    }
+    
+    const liList = document.getElementsByTagName('li');
+    
+    for (var i = 0; i<liList.length; i++) {  
+        const li = liList[i]; 
+        
+        li.innerHTML = replaceBadge(li.innerHTML, {
+            outdated: {
+                color: 'Red',
+            }
+        });
+    }
+</script>
\ No newline at end of file