diff --git a/lib/classes/component.php b/lib/classes/component.php
index 9c11544ed51..aeccbe68e4b 100644
--- a/lib/classes/component.php
+++ b/lib/classes/component.php
@@ -75,6 +75,9 @@ class core_component {
     protected static $psr4namespaces = array(
         'MaxMind' => 'lib/maxmind/MaxMind',
         'GeoIp2' => 'lib/maxmind/GeoIp2',
+        'Sabberworm\\CSS' => 'lib/php-css-parser',
+        'MoodleHQ\\RTLCSS' => 'lib/rtlcss',
+        'Leafo\\ScssPhp' => 'lib/scssphp'
     );
 
     /**
diff --git a/lib/classes/cssparser.php b/lib/classes/cssparser.php
index 9aa9238235f..b9fa160f076 100644
--- a/lib/classes/cssparser.php
+++ b/lib/classes/cssparser.php
@@ -24,40 +24,6 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-// TODO MDL-53016 Remove this when the latter is implemented.
-require_once($CFG->libdir . '/php-css-parser/Comment/Commentable.php');
-require_once($CFG->libdir . '/php-css-parser/Renderable.php');
-require_once($CFG->libdir . '/php-css-parser/Property/AtRule.php');
-require_once($CFG->libdir . '/php-css-parser/RuleSet/RuleSet.php');
-require_once($CFG->libdir . '/php-css-parser/RuleSet/AtRuleSet.php');
-require_once($CFG->libdir . '/php-css-parser/Parsing/SourceException.php');
-require_once($CFG->libdir . '/php-css-parser/CSSList/CSSList.php');
-require_once($CFG->libdir . '/php-css-parser/CSSList/CSSBlockList.php');
-require_once($CFG->libdir . '/php-css-parser/Value/Value.php');
-require_once($CFG->libdir . '/php-css-parser/Value/ValueList.php');
-require_once($CFG->libdir . '/php-css-parser/Value/CSSFunction.php');
-require_once($CFG->libdir . '/php-css-parser/Comment/Comment.php');
-require_once($CFG->libdir . '/php-css-parser/Value/PrimitiveValue.php');
-require_once($CFG->libdir . '/php-css-parser/CSSList/AtRuleBlockList.php');
-require_once($CFG->libdir . '/php-css-parser/CSSList/Document.php');
-require_once($CFG->libdir . '/php-css-parser/CSSList/KeyFrame.php');
-require_once($CFG->libdir . '/php-css-parser/OutputFormat.php');
-require_once($CFG->libdir . '/php-css-parser/Parser.php');
-require_once($CFG->libdir . '/php-css-parser/Parsing/OutputException.php');
-require_once($CFG->libdir . '/php-css-parser/Parsing/UnexpectedTokenException.php');
-require_once($CFG->libdir . '/php-css-parser/Property/Charset.php');
-require_once($CFG->libdir . '/php-css-parser/Property/CSSNamespace.php');
-require_once($CFG->libdir . '/php-css-parser/Property/Import.php');
-require_once($CFG->libdir . '/php-css-parser/Property/Selector.php');
-require_once($CFG->libdir . '/php-css-parser/Rule/Rule.php');
-require_once($CFG->libdir . '/php-css-parser/RuleSet/DeclarationBlock.php');
-require_once($CFG->libdir . '/php-css-parser/Settings.php');
-require_once($CFG->libdir . '/php-css-parser/Value/Color.php');
-require_once($CFG->libdir . '/php-css-parser/Value/CSSString.php');
-require_once($CFG->libdir . '/php-css-parser/Value/RuleValueList.php');
-require_once($CFG->libdir . '/php-css-parser/Value/Size.php');
-require_once($CFG->libdir . '/php-css-parser/Value/URL.php');
-
 /**
  * Moodle CSS parser.
  *
diff --git a/lib/classes/rtlcss.php b/lib/classes/rtlcss.php
index 986d4cbd754..29fc944d4e3 100644
--- a/lib/classes/rtlcss.php
+++ b/lib/classes/rtlcss.php
@@ -24,9 +24,6 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-// TODO MDL-53016 Remove this when the latter is implemented.
-require_once($CFG->libdir . '/rtlcss/RTLCSS.php');
-
 /**
  * Moodle RTLCSS class.
  *
diff --git a/lib/classes/scss.php b/lib/classes/scss.php
index 7479d9c73e5..e60b8e0a8fe 100644
--- a/lib/classes/scss.php
+++ b/lib/classes/scss.php
@@ -24,31 +24,6 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-// TODO MDL-53016 Remove this when the latter is implemented.
-require_once($CFG->libdir . '/scssphp/Base/Range.php');
-require_once($CFG->libdir . '/scssphp/Block.php');
-require_once($CFG->libdir . '/scssphp/Colors.php');
-require_once($CFG->libdir . '/scssphp/Compiler.php');
-require_once($CFG->libdir . '/scssphp/Compiler/Environment.php');
-require_once($CFG->libdir . '/scssphp/Exception/CompilerException.php');
-require_once($CFG->libdir . '/scssphp/Exception/ParserException.php');
-require_once($CFG->libdir . '/scssphp/Exception/ServerException.php');
-require_once($CFG->libdir . '/scssphp/Formatter.php');
-require_once($CFG->libdir . '/scssphp/Formatter/Compact.php');
-require_once($CFG->libdir . '/scssphp/Formatter/Compressed.php');
-require_once($CFG->libdir . '/scssphp/Formatter/Crunched.php');
-require_once($CFG->libdir . '/scssphp/Formatter/Debug.php');
-require_once($CFG->libdir . '/scssphp/Formatter/Expanded.php');
-require_once($CFG->libdir . '/scssphp/Formatter/Nested.php');
-require_once($CFG->libdir . '/scssphp/Formatter/OutputBlock.php');
-require_once($CFG->libdir . '/scssphp/Node.php');
-require_once($CFG->libdir . '/scssphp/Node/Number.php');
-require_once($CFG->libdir . '/scssphp/Parser.php');
-require_once($CFG->libdir . '/scssphp/Type.php');
-require_once($CFG->libdir . '/scssphp/Util.php');
-require_once($CFG->libdir . '/scssphp/Version.php');
-require_once($CFG->libdir . '/scssphp/Server.php');
-
 /**
  * Moodle SCSS compiler class.
  *