diff --git a/lib/plugins/filter/after_post_render/external_link.js b/lib/plugins/filter/after_post_render/external_link.js
index 10a0c0a3b2..c7e2469051 100644
--- a/lib/plugins/filter/after_post_render/external_link.js
+++ b/lib/plugins/filter/after_post_render/external_link.js
@@ -1,25 +1,17 @@
 'use strict';
 
-const { URL } = require('url');
-
-const urlObj = (str) => {
-  try {
-    return new URL(str);
-  } catch (err) {
-    return str;
-  }
-};
+const { parse, URL } = require('url');
 
 const isExternal = (url, config) => {
-  const exclude = Array.isArray(config.external_link.exclude) ? config.external_link.exclude
-    : [config.external_link.exclude];
-  const data = urlObj(url);
-  const host = data.hostname;
-  const sitehost = typeof urlObj(config.url) === 'object' ? urlObj(config.url).hostname : config.url;
+  const { exclude } = config.external_link;
+  const sitehost = parse(config.url).hostname || config.url;
+  // some little dirty hacks
+  const data = new URL(url, `http://${sitehost}`);
 
   if (!sitehost || typeof data === 'string') return false;
   if (data.origin === 'null') return false;
 
+  const host = data.hostname;
   if (exclude && exclude.length) {
     for (const i of exclude) {
       if (host === i) return false;
@@ -45,10 +37,13 @@ function externalLinkFilter(data) {
   if (config.external_link === false || config.external_link.enable === false
     || config.external_link.field !== 'post') return;
 
+  config.external_link.exclude = Array.isArray(config.external_link.exclude) ? config.external_link.exclude
+    : [config.external_link.exclude];
+
   data.content = data.content.replace(/<a.*?(href=['"](.*?)['"]).*?>/gi, (str, hrefStr, href) => {
-    if (/target=/gi.test(str) || !isExternal(href, config)) return str;
+    if (str.includes('target=') || !isExternal(href, config)) return str;
 
-    if (/rel=/gi.test(str)) {
+    if (str.includes('rel=')) {
       str = str.replace(/rel="(.*?)"/gi, (relStr, rel) => {
         if (!rel.includes('noopenner')) relStr = relStr.replace(rel, `${rel} noopener`);
         return relStr;
diff --git a/lib/plugins/filter/after_render/external_link.js b/lib/plugins/filter/after_render/external_link.js
index 92ed1f57fa..dfdec89f85 100644
--- a/lib/plugins/filter/after_render/external_link.js
+++ b/lib/plugins/filter/after_render/external_link.js
@@ -1,14 +1,6 @@
 'use strict';
 
-const { URL } = require('url');
-
-const urlObj = (str) => {
-  try {
-    return new URL(str);
-  } catch (err) {
-    return str;
-  }
-};
+const { parse, URL } = require('url');
 
 /**
  * Check whether the link is external
@@ -17,15 +9,15 @@ const urlObj = (str) => {
  * @returns {Boolean} True if the link doesn't have protocol or link has same host with config.url
  */
 const isExternal = (url, config) => {
-  const exclude = Array.isArray(config.external_link.exclude) ? config.external_link.exclude
-    : [config.external_link.exclude];
-  const data = urlObj(url);
-  const host = data.hostname;
-  const sitehost = typeof urlObj(config.url) === 'object' ? urlObj(config.url).hostname : config.url;
+  const { exclude } = config.external_link;
+  const sitehost = parse(config.url).hostname || config.url;
+  // some little dirty hacks
+  const data = new URL(url, `http://${sitehost}`);
 
   if (!sitehost || typeof data === 'string') return false;
   if (data.origin === 'null') return false;
 
+  const host = data.hostname;
   if (exclude && exclude.length) {
     for (const i of exclude) {
       if (host === i) return false;
@@ -51,10 +43,13 @@ function externalLinkFilter(data) {
   if (config.external_link === false || config.external_link.enable === false
     || config.external_link.field !== 'site') return;
 
+  config.external_link.exclude = Array.isArray(config.external_link.exclude) ? config.external_link.exclude
+    : [config.external_link.exclude];
+
   data = data.replace(/<a.*?(href=['"](.*?)['"]).*?>/gi, (str, hrefStr, href) => {
-    if (/target=/gi.test(str) || !isExternal(href, config)) return str;
+    if (str.includes('target=') || !isExternal(href, config)) return str;
 
-    if (/rel=/gi.test(str)) {
+    if (str.includes('rel=')) {
       str = str.replace(/rel="(.*?)"/gi, (relStr, rel) => {
         if (!rel.includes('noopenner')) relStr = relStr.replace(rel, `${rel} noopener`);
         return relStr;