diff --git a/core/modules/simpletest/tests/src/FunctionalJavascript/BrowserWithJavascriptTest.php b/core/modules/simpletest/tests/src/FunctionalJavascript/BrowserWithJavascriptTest.php
index 572a842..2439799 100644
--- a/core/modules/simpletest/tests/src/FunctionalJavascript/BrowserWithJavascriptTest.php
+++ b/core/modules/simpletest/tests/src/FunctionalJavascript/BrowserWithJavascriptTest.php
@@ -53,4 +53,13 @@ public function testAssertJsCondition() {
     $this->assertJsCondition($javascript, 100);
   }
 
+  /**
+   * Tests creating screenshots.
+   */
+  public function testCreateScreenshot() {
+    $this->drupalGet('<front>');
+    $this->createScreenshot('public://screenshot.jpg');
+    $this->assertFileExists('public://screenshot.jpg');
+  }
+
 }
diff --git a/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php b/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php
index 116bd32..2c2ac3a 100644
--- a/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php
@@ -103,6 +103,29 @@ protected function assertJsCondition($condition, $timeout = 1000, $message = '')
   }
 
   /**
+   * Creates a screenshot.
+   *
+   * @param string $filename
+   *   The file name of the resulting screenshot. If using the default phantomjs
+   *   driver then this should be a JPG filename.
+   * @param string $background_color
+   *   (optional) Background color name.
+   *
+   * @throws \Behat\Mink\Exception\UnsupportedDriverActionException
+   *   When operation not supported by the driver.
+   * @throws \Behat\Mink\Exception\DriverException
+   *   When the operation cannot be done.
+   */
+  protected function createScreenshot($filename, $background_color = 'white') {
+    $session = $this->getSession();
+    if (!empty($background_color)) {
+      $session->executeScript("document.body.style.backgroundColor = '" . $background_color . "';");
+    }
+    $image = $session->getScreenshot();
+    file_put_contents($filename, $image);
+  }
+
+  /**
    * {@inheritdoc}
    */
   public function assertSession($name = NULL) {