diff --git a/core/lib/Drupal/Core/Template/TwigNodeTrans.php b/core/lib/Drupal/Core/Template/TwigNodeTrans.php
index 1bacb9e..a7b723a 100644
--- a/core/lib/Drupal/Core/Template/TwigNodeTrans.php
+++ b/core/lib/Drupal/Core/Template/TwigNodeTrans.php
@@ -82,20 +82,7 @@ public function compile(\Twig_Compiler $compiler) {
     // Write function closure.
     $compiler->raw(')');
 
-    // Append translation debug markup, if necessary.
-    if ($compiler->getEnvironment()->isDebug()) {
-      $compiler->raw(" . '\n<!-- TRANSLATION: ");
-      $compiler->subcompile($singular);
-      if (!empty($plural)) {
-        $compiler->raw(', PLURAL: ')->subcompile($plural);
-      }
-      if (!empty($options)) {
-        foreach ($options->getKeyValuePairs() as $pair) {
-          $compiler->raw(', ' . Unicode::strtoupper($pair['key']->getAttribute('value')) . ': ')->subcompile($pair['value']);
-        }
-      }
-      $compiler->raw(" -->\n'");
-    }
+    // @todo Add debug output, see https://www.drupal.org/node/2512672
 
     // End writing.
     $compiler->raw(";\n");
diff --git a/core/modules/system/src/Tests/Theme/TwigTransTest.php b/core/modules/system/src/Tests/Theme/TwigTransTest.php
index d9d3aa56..1190ab5 100644
--- a/core/modules/system/src/Tests/Theme/TwigTransTest.php
+++ b/core/modules/system/src/Tests/Theme/TwigTransTest.php
@@ -154,9 +154,12 @@ public function testTwigTransTags() {
       'O HAI NU TXTZZZZ.',
       '{% trans with {"context": "Lolspeak", "langcode": "zz"} %} was successfully translated with context in specified language.'
     );
-
-    // Ensure debug output does not print.
-    $this->checkForDebugMarkup(FALSE);
+    // Makes sure https://www.drupal.org/node/2489024 doesn't happen without
+    // twig debug.
+    $this->assertText(
+      "Hello kittens - ' . print('I am bad code!') . '",
+      'Running php code inside a Twig trans is not possible.'
+    );
   }
 
   /**
@@ -172,53 +175,6 @@ public function testTwigTransDebug() {
 
     // Get page for assertion testing.
     $this->drupalGet('twig-theme-test/trans', array('language' => \Drupal::languageManager()->getLanguage('xx')));
-
-    // Ensure debug output is printed.
-    $this->checkForDebugMarkup(TRUE);
-  }
-
-  /**
-   * Tests rendering a placeholder outside of translate.
-   *
-   * This test ensures that the security problem described in
-   * https://www.drupal.org/node/2495179 doesn't exist.
-   */
-  public function testPlaceholderOutsideOfTrans() {
-    $this->drupalGet(Url::fromRoute('twig_theme_test.placeholder_outside_trans'));
-
-    $script = '<script>alert(123);</script>';
-    $this->assertNoRaw($script);
-    $this->assertEqual(2, substr_count($this->getRawContent(), '<em class="placeholder">' . SafeMarkup::checkPlain($script) . '</em>'));
-  }
-
-  /**
-   * Helper function: test twig debug translation markup.
-   *
-   * @param bool $visible
-   *   Toggle determining which assertion to use for test.
-   */
-  protected function checkForDebugMarkup($visible) {
-    $tests = array(
-      '{% trans "Hello sun." %}' => '<!-- TRANSLATION: "Hello sun." -->',
-      '{% trans "Hello sun." with {"context": "Lolspeak"} %}' => '<!-- TRANSLATION: "Hello sun.", CONTEXT: "Lolspeak" -->',
-      '{{ "Hello moon."|trans }}' => '<!-- TRANSLATION: "Hello moon." -->',
-      '{% trans %} with {% plural %}' => '<!-- TRANSLATION: "Hello star.", PLURAL: "Hello @count stars." -->',
-      '{{ token }}' => '<!-- TRANSLATION: "Escaped: @string" -->',
-      '{{ token|passthrough }}' => '<!-- TRANSLATION: "Pass-through: !string" -->',
-      '{{ token|placeholder }}' => '<!-- TRANSLATION: "Placeholder: %string" -->',
-      '{{ complex.tokens }}' => '<!-- TRANSLATION: "This @token.name has a length of: @count. It contains: %token.numbers and @token.bad_text. Lets pass the bad text through: !token.bad_text." -->',
-      '{% trans with {"context": "Lolspeak"} %}I have context.{% endtrans %}' => '<!-- TRANSLATION: "I have context.", CONTEXT: "Lolspeak" -->',
-      '{% trans with {"langcode": "zz"} %}Hello new text.{% endtrans %}' => '<!-- TRANSLATION: "Hello new text.", LANGCODE: "zz" -->',
-      '{% trans with {"context": "Lolspeak", "langcode": "zz"} %}Hello new text.{% endtrans %}' => '<!-- TRANSLATION: "Hello new text.", CONTEXT: "Lolspeak", LANGCODE: "zz" -->',
-    );
-    foreach ($tests as $test => $markup) {
-      if ($visible) {
-        $this->assertRaw($markup, "Twig debug translation markup exists in source for: $test");
-      }
-      else {
-        $this->assertNoRaw($markup, "Twig debug translation markup does not exist in source for: $test");
-      }
-    }
   }
 
   /**
diff --git a/core/modules/system/tests/modules/twig_theme_test/templates/twig_theme_test.trans.html.twig b/core/modules/system/tests/modules/twig_theme_test/templates/twig_theme_test.trans.html.twig
index 2f4dda0..16b14dd 100644
--- a/core/modules/system/tests/modules/twig_theme_test/templates/twig_theme_test.trans.html.twig
+++ b/core/modules/system/tests/modules/twig_theme_test/templates/twig_theme_test.trans.html.twig
@@ -94,3 +94,10 @@
     Hello new text.
   {% endtrans %}
 </div>
+
+{# Tests that https://www.drupal.org/node/2489024 doesn't happen without twig debug. #}
+<div>
+  '{% trans %}
+  Hello kittens - ' . print('I am bad code!') . '
+  {% endtrans %}
+</div>