diff --git a/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php b/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php
index 5785a7d..f0ee8e7 100644
--- a/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php
+++ b/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php
@@ -94,7 +94,7 @@ protected function assertNoText($text) {
   }
 
   /**
-   * Passes if the text is found ONLY ONCE on the text version of the page.
+   * Passes if the text is found only once on the text version of the page.
    *
    * The text version is the equivalent of what a user would see when viewing
    * through a web browser. In other words the HTML has been filtered out of
@@ -115,12 +115,12 @@ protected function assertUniqueText($text, $message = NULL) {
 
     $message = $message ?: "'$text' found only once on the page";
     $page_text = $this->getSession()->getPage()->getText();
-    $nr_found = substr_count($page_text, $text);
-    $this->assertSame(1, $nr_found, $message);
+    $occurrences = substr_count($page_text, $text);
+    $this->assertSame(1, $occurrences, $message);
   }
 
   /**
-   * Passes if the text is found MORE THAN ONCE on the text version of the page.
+   * Passes if the text is found more tjan once on the text version of the page.
    *
    * The text version is the equivalent of what a user would see when viewing
    * through a web browser. In other words the HTML has been filtered out of
@@ -141,8 +141,8 @@ protected function assertNoUniqueText($text, $message = '') {
 
     $message = $message ?: "'$text' found more than once on the page";
     $page_text = $this->getSession()->getPage()->getText();
-    $nr_found = substr_count($page_text, $text);
-    $this->assertGreaterThan(1, $nr_found, $message);
+    $occurrences = substr_count($page_text, $text);
+    $this->assertGreaterThan(1, $occurrences, $message);
   }
 
   /**
@@ -189,12 +189,17 @@ protected function assertFieldByName($name, $value = NULL) {
    *   (optional) Value of the field to assert. You may pass in NULL (default)
    *   to skip checking the actual value, while still checking that the field
    *   exists.
+   * @param string $message
+   *   (optional) A message to display with the assertion. Do not translate
+   *   messages: use \Drupal\Component\Utility\SafeMarkup::format() to embed
+   *   variables in the message text, not t(). If left blank, a default message
+   *   will be displayed.
    *
    * @deprecated Scheduled for removal in Drupal 9.0.0.
    *   Use $this->assertSession()->fieldNotExists() or
    *   $this->assertSession()->fieldValueNotEquals() instead.
    */
-  protected function assertNoFieldByName($name, $value = NULL) {
+  protected function assertNoFieldByName($name, $value = NULL, $message = '') {
     $this->assertSession()->fieldNotExists($name);
     if ($value !== NULL) {
       $this->assertSession()->fieldValueNotEquals($name, (string) $value);
@@ -442,11 +447,16 @@ protected function assertOptionSelected($id, $option, $message = NULL) {
    *
    * @param string $id
    *   ID of field to assert.
+   * @param string $message
+   *   (optional) A message to display with the assertion. Do not translate
+   *   messages: use \Drupal\Component\Utility\SafeMarkup::format() to embed
+   *   variables in the message text, not t(). If left blank, a default message
+   *   will be displayed.
    *
    * @deprecated Scheduled for removal in Drupal 9.0.0.
    *   Use $this->assertSession()->checkboxChecked() instead.
    */
-  protected function assertFieldChecked($id) {
+  protected function assertFieldChecked($id, $message = '') {
     $this->assertSession()->checkboxChecked($id);
   }
 
@@ -455,11 +465,16 @@ protected function assertFieldChecked($id) {
    *
    * @param string $id
    *   ID of field to assert.
+   * @param string $message
+   *   (optional) A message to display with the assertion. Do not translate
+   *   messages: use \Drupal\Component\Utility\SafeMarkup::format() to embed
+   *   variables in the message text, not t(). If left blank, a default message
+   *   will be displayed.
    *
    * @deprecated Scheduled for removal in Drupal 9.0.0.
    *   Use $this->assertSession()->checkboxNotChecked() instead.
    */
-  protected function assertNoFieldChecked($id) {
+  protected function assertNoFieldChecked($id, $message = '') {
     $this->assertSession()->checkboxNotChecked($id);
   }
 
@@ -498,11 +513,16 @@ protected function assertNoEscaped($raw) {
    *
    * @param string $pattern
    *   Perl regex to look for including the regex delimiters.
+   * @param string $message
+   *   (optional) A message to display with the assertion. Do not translate
+   *   messages: use \Drupal\Component\Utility\SafeMarkup::format() to embed
+   *   variables in the message text, not t(). If left blank, a default message
+   *   will be displayed.
    *
    * @deprecated Scheduled for removal in Drupal 9.0.0.
    *   Use $this->assertSession()->responseMatches() instead.
    */
-  protected function assertPattern($pattern) {
+  protected function assertPattern($pattern, $message = '') {
     $this->assertSession()->responseMatches($pattern);
   }