diff --git a/lib/plugins/filter/after_render/injector.js b/lib/plugins/filter/after_render/injector.js
index 97cc3e844c..477f344dad 100644
--- a/lib/plugins/filter/after_render/injector.js
+++ b/lib/plugins/filter/after_render/injector.js
@@ -40,28 +40,26 @@ function injectFilter(data, locals = { page: {} }) {
   };
 
   function injector(data, pattern, flag, isBegin = true) {
-    return data.replace(pattern, str => {
-      if (data.includes(`hexo injector ${flag}`)) return str;
+    if (data.includes(`hexo injector ${flag}`)) return data;
 
-      const arr = _Injector.get(flag).filter(i => is(i.to)).map(i => i.value);
+    const arr = _Injector.get(flag).filter(i => is(i.to)).map(i => i.value);
 
-      if (arr.length) {
-        const code = arr.reduce((a, c) => a + c, '');
+    if (!arr.length) return data;
 
-        if (isBegin) {
-          return str
-            + '<!-- hexo injector ' + flag + ' start -->'
-            + code
-            + '<!-- hexo injector ' + flag + ' end -->';
-        }
+    return data.replace(pattern, str => {
+      const code = arr.reduce((a, c) => a + c, '');
 
-        return '<!-- hexo injector ' + flag + ' start -->'
+      if (isBegin) {
+        return str
+          + '<!-- hexo injector ' + flag + ' start -->'
           + code
-          + '<!-- hexo injector ' + flag + ' end -->'
-          + str;
+          + '<!-- hexo injector ' + flag + ' end -->';
       }
 
-      return str;
+      return '<!-- hexo injector ' + flag + ' start -->'
+        + code
+        + '<!-- hexo injector ' + flag + ' end -->'
+        + str;
     });
   }