diff --git a/src/config/load.ts b/src/config/load.ts
index 1c59f82b3..8929cf8d3 100644
--- a/src/config/load.ts
+++ b/src/config/load.ts
@@ -53,5 +53,5 @@ export default function load() {
 }
 
 function normalizeUrl(url: string) {
-	return url[url.length - 1] === '/' ? url.substr(0, url.length - 1) : url;
+	return url.endsWith('/') ? url.substr(0, url.length - 1) : url;
 }
diff --git a/src/server/api/service/twitter.ts b/src/server/api/service/twitter.ts
index 8c668e832..aad2846bb 100644
--- a/src/server/api/service/twitter.ts
+++ b/src/server/api/service/twitter.ts
@@ -14,7 +14,7 @@ function getUserToken(ctx: Koa.Context) {
 
 function compareOrigin(ctx: Koa.Context) {
 	function normalizeUrl(url: string) {
-		return url[url.length - 1] === '/' ? url.substr(0, url.length - 1) : url;
+		return url.endsWith('/') ? url.substr(0, url.length - 1) : url;
 	}
 
 	const referer = ctx.headers['referer'];
diff --git a/webpack/loaders/replace.js b/webpack/loaders/replace.js
index fd6bb3617..9f4825e18 100644
--- a/webpack/loaders/replace.js
+++ b/webpack/loaders/replace.js
@@ -7,7 +7,7 @@ function trim(text, g) {
 export default function(src) {
 	const fn = options => {
 		const search = options.search;
-		const g = search[search.length - 1] == 'g';
+		const g = search.endsWith('g');
 		const file = this.resourcePath.replace(/\\/g, '/');
 		const replace = options.i18n ? global[options.replace].bind(null, {
 			src: file,