diff --git a/core/lib/Drupal/Core/Template/TwigEnvironment.php b/core/lib/Drupal/Core/Template/TwigEnvironment.php
index c64956cfcd..34df39f099 100644
--- a/core/lib/Drupal/Core/Template/TwigEnvironment.php
+++ b/core/lib/Drupal/Core/Template/TwigEnvironment.php
@@ -13,6 +13,7 @@
 use Twig\Error\SyntaxError;
 use Twig\Extension\SandboxExtension;
 use Twig\Loader\LoaderInterface;
+use Twig\Source;
 
 /**
  * A class that defines a Twig environment for Drupal.
@@ -104,13 +105,7 @@ public function __construct($root, CacheBackendInterface $cache, $twig_extension
   /**
    * {@inheritdoc}
    */
-  public function compileSource($source, $name = NULL) {
-    if (!$source instanceof \Twig_Source) {
-      // @codingStandardsIgnoreLine (Twig deprecation).
-      @trigger_error(sprintf('Passing a string as the $source argument of %s() is deprecated since version 1.27. Pass a Twig\Source instance instead.', __METHOD__), E_USER_DEPRECATED);
-      $source = new \Twig_Source($source, $name);
-    }
-
+  public function compileSource(Source $source) {
     // Note: always use \Drupal\Core\Serialization\Yaml here instead of the
     // "serializer.yaml" service. This allows the core serializer to utilize
     // core related functionality which isn't available as the standalone
@@ -124,7 +119,7 @@ public function compileSource($source, $name = NULL) {
     try {
       if (($line = $frontMatter->getLine()) > 1) {
         $content = "{% line $line %}" . $frontMatter->getContent();
-        $source = new \Twig_Source($content, $source->getName(), $source->getPath());
+        $source = new Source($content, $source->getName(), $source->getPath());
       }
     }
     catch (FrontMatterParseException $exception) {
@@ -134,7 +129,7 @@ public function compileSource($source, $name = NULL) {
       throw new SyntaxError($message, $exception->getSourceLine(), $source, $exception);
     }
 
-    return parent::compileSource($source, $name);
+    return parent::compileSource($source);
   }
 
   /**
@@ -169,13 +164,10 @@ public function getTwigCachePrefix() {
    *
    * @throws \Twig\Error\LoaderError
    * @throws \Twig\Error\SyntaxError
-   *
-   * @todo Simplify this method to just use $loader->getSourceContext($name).
-   * @see https://www.drupal.org/project/drupal/issues/3041076
    */
   public function getTemplateMetadata(string $name): array {
     $loader = $this->getLoader();
-    $source = $loader instanceof \Twig_SourceContextLoaderInterface ? $loader->getSourceContext($name) : new \Twig_Source($loader->getSource($name), $name);
+    $source = $loader->getSourceContext($name);
 
     // Note: always use \Drupal\Core\Serialization\Yaml here instead of the
     // "serializer.yaml" service. This allows the core serializer to utilize
diff --git a/core/tests/Drupal/KernelTests/Core/Theme/FrontMatterTest.php b/core/tests/Drupal/KernelTests/Core/Theme/FrontMatterTest.php
index 0f857dba98..f902547dce 100644
--- a/core/tests/Drupal/KernelTests/Core/Theme/FrontMatterTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Theme/FrontMatterTest.php
@@ -70,10 +70,10 @@ protected function createTwigTemplate(string $content = ''): string {
    * @covers \Drupal\Component\FrontMatter\Exception\FrontMatterParseException
    */
   public function testFrontMatterBroken() {
-    $source = "---\nbroken: {\n---\n" . ComponentFrontMatterTest::SOURCE;
+    $source = "---\ncollection:\n-  key: foo\n  foo: bar\n---\n" . ComponentFrontMatterTest::SOURCE;
     $file = $this->createTwigTemplate($source);
     $this->expectException(SyntaxError::class);
-    $this->expectExceptionMessage('An error occurred when attempting to parse front matter data on line 3 in ' . $file);
+    $this->expectExceptionMessage('An error occurred when attempting to parse front matter data on line 4 in ' . $file);
     $this->twig->getTemplateMetadata(basename($file));
   }
 
diff --git a/core/tests/Drupal/Tests/Component/FrontMatter/FrontMatterTest.php b/core/tests/Drupal/Tests/Component/FrontMatter/FrontMatterTest.php
index 47de2bf177..3e6a27aabf 100644
--- a/core/tests/Drupal/Tests/Component/FrontMatter/FrontMatterTest.php
+++ b/core/tests/Drupal/Tests/Component/FrontMatter/FrontMatterTest.php
@@ -64,8 +64,8 @@ public function testFrontMatterSerializerException() {
    */
   public function testFrontMatterBroken() {
     $this->expectException(FrontMatterParseException::class);
-    $this->expectExceptionMessage('An error occurred when attempting to parse front matter data on line 3');
-    $source = "---\nbroken: {\n---\n";
+    $this->expectExceptionMessage('An error occurred when attempting to parse front matter data on line 4');
+    $source = "---\ncollection:\n-  key: foo\n  foo: bar\n---\n";
     FrontMatter::create($source)->getData();
   }