diff --git a/src/wp-admin/admin-footer.php b/src/wp-admin/admin-footer.php
index 9e683d0b117ba..ec149ef45d66d 100644
--- a/src/wp-admin/admin-footer.php
+++ b/src/wp-admin/admin-footer.php
@@ -114,6 +114,6 @@
 ?>
 
 <div class="clear"></div></div><!-- wpwrap -->
-<script type="text/javascript">if(typeof wpOnload==='function')wpOnload();</script>
+<?php wp_print_inline_script_tag( "if(typeof wpOnload==='function')wpOnload();" ); ?>
 </body>
 </html>
diff --git a/src/wp-admin/admin-header.php b/src/wp-admin/admin-header.php
index fc836c20a2c1d..7c8340df57c43 100644
--- a/src/wp-admin/admin-header.php
+++ b/src/wp-admin/admin-header.php
@@ -95,8 +95,10 @@
 wp_enqueue_script( 'svg-painter' );
 
 $admin_body_class = preg_replace( '/[^a-z0-9_-]+/i', '-', $hook_suffix );
+
+ob_start();
 ?>
-<script type="text/javascript">
+<script>
 addLoadEvent = function(func){if(typeof jQuery!=='undefined')jQuery(function(){func();});else if(typeof wpOnload!=='function'){wpOnload=func;}else{var oldonload=wpOnload;wpOnload=function(){oldonload();func();}}};
 var ajaxurl = '<?php echo esc_js( admin_url( 'admin-ajax.php', 'relative' ) ); ?>',
 	pagenow = '<?php echo esc_js( $current_screen->id ); ?>',
@@ -107,6 +109,7 @@
 	isRtl = <?php echo (int) is_rtl(); ?>;
 </script>
 <?php
+wp_print_inline_script_tag( trim( str_replace( array( '<script>', '</script>' ), '', ob_get_clean() ) ) );
 
 /**
  * Fires when enqueuing scripts for all admin pages.
@@ -243,9 +246,8 @@
 $admin_body_classes = ltrim( $admin_body_classes . ' ' . $admin_body_class );
 ?>
 <body class="wp-admin wp-core-ui no-js <?php echo esc_attr( $admin_body_classes ); ?>">
-<script type="text/javascript">
-	document.body.className = document.body.className.replace('no-js','js');
-</script>
+
+<?php wp_print_inline_script_tag( "document.body.className = document.body.className.replace('no-js','js');" ); ?>
 
 <?php
 // Make sure the customize body classes are correct as early as possible.
diff --git a/src/wp-admin/includes/media.php b/src/wp-admin/includes/media.php
index 0910693fc9810..e3839362864cc 100644
--- a/src/wp-admin/includes/media.php
+++ b/src/wp-admin/includes/media.php
@@ -547,13 +547,16 @@ function wp_iframe( $content_func, ...$args ) {
 		wp_enqueue_style( 'deprecated-media' );
 	}
 
+	ob_start();
 	?>
-	<script type="text/javascript">
+	<script>
 	addLoadEvent = function(func){if(typeof jQuery!=='undefined')jQuery(function(){func();});else if(typeof wpOnload!=='function'){wpOnload=func;}else{var oldonload=wpOnload;wpOnload=function(){oldonload();func();}}};
 	var ajaxurl = '<?php echo esc_js( admin_url( 'admin-ajax.php', 'relative' ) ); ?>', pagenow = 'media-upload-popup', adminpage = 'media-upload-popup',
 	isRtl = <?php echo (int) is_rtl(); ?>;
 	</script>
 	<?php
+	wp_print_inline_script_tag( trim( str_replace( array( '<script>', '</script>' ), '', ob_get_clean() ) ) );
+
 	/** This action is documented in wp-admin/admin-header.php */
 	do_action( 'admin_enqueue_scripts', 'media-upload-popup' );
 
@@ -610,9 +613,7 @@ function wp_iframe( $content_func, ...$args ) {
 	?>
 	</head>
 	<body<?php echo $body_id_attr; ?> class="wp-core-ui no-js">
-	<script type="text/javascript">
-	document.body.className = document.body.className.replace('no-js', 'js');
-	</script>
+	<?php wp_print_inline_script_tag( "document.body.className = document.body.className.replace('no-js','js');" ); ?>
 	<?php
 
 	call_user_func_array( $content_func, $args );
@@ -621,7 +622,7 @@ function wp_iframe( $content_func, ...$args ) {
 	do_action( 'admin_print_footer_scripts' );
 
 	?>
-	<script type="text/javascript">if(typeof wpOnload==='function')wpOnload();</script>
+	<?php wp_print_inline_script_tag( "if(typeof wpOnload==='function')wpOnload();" ); ?>
 	</body>
 	</html>
 	<?php
diff --git a/src/wp-admin/includes/misc.php b/src/wp-admin/includes/misc.php
index 24cd26d661842..1fdaa2b9c7986 100644
--- a/src/wp-admin/includes/misc.php
+++ b/src/wp-admin/includes/misc.php
@@ -1085,7 +1085,9 @@ function wp_color_scheme_settings() {
 		);
 	}
 
-	echo '<script type="text/javascript">var _wpColorScheme = ' . wp_json_encode( array( 'icons' => $icon_colors ) ) . ";</script>\n";
+	wp_print_inline_script_tag(
+		sprintf( 'var _wpColorScheme = %s;', wp_json_encode( array( 'icons' => $icon_colors ) ) )
+	);
 }
 
 /**
@@ -1400,12 +1402,14 @@ function wp_admin_canonical_url() {
 	$filtered_url = remove_query_arg( $removable_query_args, $current_url );
 	?>
 	<link id="wp-admin-canonical" rel="canonical" href="<?php echo esc_url( $filtered_url ); ?>" />
+	<?php ob_start(); ?>
 	<script>
 		if ( window.history.replaceState ) {
 			window.history.replaceState( null, null, document.getElementById( 'wp-admin-canonical' ).href + window.location.hash );
 		}
 	</script>
 	<?php
+	wp_print_inline_script_tag( trim( str_replace( array( '<script>', '</script>' ), '', ob_get_clean() ) ) );
 }
 
 /**
diff --git a/src/wp-admin/includes/template.php b/src/wp-admin/includes/template.php
index 2394fbb6f2084..0c70c54cf8a6b 100644
--- a/src/wp-admin/includes/template.php
+++ b/src/wp-admin/includes/template.php
@@ -2124,8 +2124,9 @@ function iframe_header( $title = '', $deprecated = false ) {
 <title><?php bloginfo( 'name' ); ?> &rsaquo; <?php echo $title; ?> &#8212; <?php _e( 'WordPress' ); ?></title>
 	<?php
 	wp_enqueue_style( 'colors' );
+	ob_start();
 	?>
-<script type="text/javascript">
+<script>
 addLoadEvent = function(func){if(typeof jQuery!=='undefined')jQuery(function(){func();});else if(typeof wpOnload!=='function'){wpOnload=func;}else{var oldonload=wpOnload;wpOnload=function(){oldonload();func();}}};
 function tb_close(){var win=window.dialogArguments||opener||parent||top;win.tb_remove();}
 var ajaxurl = '<?php echo esc_js( admin_url( 'admin-ajax.php', 'relative' ) ); ?>',
@@ -2137,6 +2138,8 @@ function tb_close(){var win=window.dialogArguments||opener||parent||top;win.tb_r
 	isRtl = <?php echo (int) is_rtl(); ?>;
 </script>
 	<?php
+	wp_print_inline_script_tag( trim( str_replace( array( '<script>', '</script>' ), '', ob_get_clean() ) ) );
+
 	/** This action is documented in wp-admin/admin-header.php */
 	do_action( 'admin_enqueue_scripts', $hook_suffix );
 
@@ -2216,7 +2219,7 @@ function iframe_footer() {
 	do_action( 'admin_print_footer_scripts' );
 	?>
 	</div>
-<script type="text/javascript">if(typeof wpOnload==='function')wpOnload();</script>
+	<?php wp_print_inline_script_tag( "if(typeof wpOnload==='function')wpOnload();" ); ?>
 </body>
 </html>
 	<?php
diff --git a/src/wp-includes/theme.php b/src/wp-includes/theme.php
index 5ff31953b1323..1ce359769247a 100644
--- a/src/wp-includes/theme.php
+++ b/src/wp-includes/theme.php
@@ -3742,9 +3742,9 @@ function wp_customize_support_script() {
 	$admin_origin = parse_url( admin_url() );
 	$home_origin  = parse_url( home_url() );
 	$cross_domain = ( strtolower( $admin_origin['host'] ) !== strtolower( $home_origin['host'] ) );
-	$type_attr    = current_theme_supports( 'html5', 'script' ) ? '' : ' type="text/javascript"';
+	ob_start();
 	?>
-	<script<?php echo $type_attr; ?>>
+	<script>
 		(function() {
 			var request, b = document.body, c = 'className', cs = 'customize-support', rcs = new RegExp('(^|\\s+)(no-)?'+cs+'(\\s+|$)');
 
@@ -3760,6 +3760,7 @@ function wp_customize_support_script() {
 		}());
 	</script>
 	<?php
+	wp_print_inline_script_tag( trim( str_replace( array( '<script>', '</script>' ), '', ob_get_clean() ) ) );
 }
 
 /**
diff --git a/src/wp-login.php b/src/wp-login.php
index 3dbfacfd2bb25..9b9b86143b17e 100644
--- a/src/wp-login.php
+++ b/src/wp-login.php
@@ -193,9 +193,7 @@ function login_header( $title = 'Log In', $message = '', $wp_error = null ) {
 	?>
 	</head>
 	<body class="login no-js <?php echo esc_attr( implode( ' ', $classes ) ); ?>">
-	<script type="text/javascript">
-		document.body.className = document.body.className.replace('no-js','js');
-	</script>
+	<?php wp_print_inline_script_tag( "document.body.className = document.body.className.replace('no-js','js');" ); ?>
 	<?php
 	/**
 	 * Fires in the login page header after the body tag is opened.
@@ -383,12 +381,14 @@ function login_footer( $input_id = '' ) {
 	<?php
 
 	if ( ! empty( $input_id ) ) {
+		ob_start();
 		?>
-		<script type="text/javascript">
+		<script>
 		try{document.getElementById('<?php echo $input_id; ?>').focus();}catch(e){}
 		if(typeof wpOnload==='function')wpOnload();
 		</script>
 		<?php
+		wp_print_inline_script_tag( trim( str_replace( array( '<script>', '</script>' ), '', ob_get_clean() ) ) );
 	}
 
 	/**
