diff --git a/gulpfile.ts b/gulpfile.ts
index 8a4a74d26..356996314 100644
--- a/gulpfile.ts
+++ b/gulpfile.ts
@@ -166,9 +166,7 @@ gulp.task('build:client:pug', [
 			.pipe(pug({
 				locals: {
 					themeColor: constants.themeColor,
-					facss: fa.dom.css(),
-					//hljscss: fs.readFileSync('./node_modules/highlight.js/styles/default.css', 'utf8')
-					hljscss: fs.readFileSync('./src/client/assets/code-highlight.css', 'utf8')
+					facss: fa.dom.css()
 				}
 			}))
 			.pipe(htmlmin({
diff --git a/src/client/app/base.pug b/src/client/app/base.pug
index 11b150bc6..ee9d4b6f6 100644
--- a/src/client/app/base.pug
+++ b/src/client/app/base.pug
@@ -34,9 +34,6 @@ html
 		//- FontAwesome style
 		style #{facss}
 
-		//- highlight.js style
-		style #{hljscss}
-
 	body
 		noscript: p
 			| JavaScriptを有効にしてください
diff --git a/src/client/app/safe.js b/src/client/app/safe.js
index 3d73fa1a9..026fc66c6 100644
--- a/src/client/app/safe.js
+++ b/src/client/app/safe.js
@@ -12,16 +12,6 @@ if (!('fetch' in window)) {
 		'To run Misskey, please update your browser to latest version or try other browsers.');
 }
 
-// Detect Edge
-if (navigator.userAgent.toLowerCase().indexOf('edge') != -1) {
-	alert(
-		'現在、お使いのブラウザ(Microsoft Edge)ではMisskeyは正しく動作しません。' +
-		'サポートしているブラウザ: Google Chrome, Mozilla Firefox, Apple Safari など' +
-		'\n\n' +
-		'Currently, Misskey cannot run correctly on your browser (Microsoft Edge). ' +
-		'Supported browsers: Google Chrome, Mozilla Firefox, Apple Safari, etc');
-}
-
 // Check whether cookie enabled
 if (!navigator.cookieEnabled) {
 	alert(
diff --git a/src/client/assets/code-highlight.css b/src/client/assets/code-highlight.css
deleted file mode 100644
index f0807dc9c..000000000
--- a/src/client/assets/code-highlight.css
+++ /dev/null
@@ -1,93 +0,0 @@
-.hljs {
-	font-family: Consolas, 'Courier New', Courier, Monaco, monospace;
-}
-
-.hljs,
-.hljs-subst {
-	color: #444;
-}
-
-.hljs-comment {
-	color: #888888;
-}
-
-.hljs-keyword {
-	color: #2973b7;
-}
-
-.hljs-number {
-	color: #ae81ff;
-}
-
-.hljs-string {
-	color: #e96900;
-}
-
-.hljs-regexp {
-	color: #e9003f;
-}
-
-.hljs-attribute,
-.hljs-selector-tag,
-.hljs-meta-keyword,
-.hljs-doctag,
-.hljs-name {
-	font-weight: bold;
-}
-
-.hljs-type,
-.hljs-selector-id,
-.hljs-selector-class,
-.hljs-quote,
-.hljs-template-tag,
-.hljs-deletion {
-	color: #880000;
-}
-
-.hljs-title,
-.hljs-section {
-	color: #880000;
-	font-weight: bold;
-}
-
-.hljs-symbol,
-.hljs-variable,
-.hljs-template-variable,
-.hljs-link,
-.hljs-selector-attr,
-.hljs-selector-pseudo {
-	color: #BC6060;
-}
-
-/* Language color: hue: 90; */
-
-.hljs-literal {
-	color: #78A960;
-}
-
-.hljs-built_in,
-.hljs-bullet,
-.hljs-code,
-.hljs-addition {
-	color: #397300;
-}
-
-/* Meta color: hue: 200 */
-
-.hljs-meta {
-	color: #1f7199;
-}
-
-.hljs-meta-string {
-	color: #4d99bf;
-}
-
-/* Misc effects */
-
-.hljs-emphasis {
-	font-style: italic;
-}
-
-.hljs-strong {
-	font-weight: bold;
-}