diff --git a/core/modules/path/src/Form/PathFormBase.php b/core/modules/path/src/Form/PathFormBase.php
index 3d8b283..b5505d0 100644
--- a/core/modules/path/src/Form/PathFormBase.php
+++ b/core/modules/path/src/Form/PathFormBase.php
@@ -152,7 +152,7 @@ public function validateForm(array &$form, FormStateInterface $form_state) {
     $source = $this->aliasManager->getPathByAlias($source);
     $alias = $form_state->getValue('alias');
     // Trim the submitted value of whitespace and slashes.
-    $alias = trim(trim($alias), '/');
+    $alias = trim($alias, " \t\n\r\0\x0B\\/");
     // Language is only set if language.module is enabled, otherwise save for all
     // languages.
     $langcode = $form_state->getValue('langcode', LanguageInterface::LANGCODE_NOT_SPECIFIED);
@@ -177,7 +177,7 @@ public function submitForm(array &$form, FormStateInterface $form_state) {
     $source = $this->aliasManager->getPathByAlias($source);
     $alias = $form_state->getValue('alias');
     // Trim the submitted value of whitespace and slashes.
-    $alias = trim(trim($alias), '/');
+    $alias = trim($alias, " \t\n\r\0\x0B\\/");
     // Language is only set if language.module is enabled, otherwise save for all
     // languages.
     $langcode = $form_state->getValue('langcode', LanguageInterface::LANGCODE_NOT_SPECIFIED);
diff --git a/core/modules/path/src/Plugin/Field/FieldWidget/PathWidget.php b/core/modules/path/src/Plugin/Field/FieldWidget/PathWidget.php
index 1a62b28..8316989 100644
--- a/core/modules/path/src/Plugin/Field/FieldWidget/PathWidget.php
+++ b/core/modules/path/src/Plugin/Field/FieldWidget/PathWidget.php
@@ -85,7 +85,7 @@ public function formElement(FieldItemListInterface $items, $delta, array $elemen
    */
   public static function validateFormElement(array &$element, FormStateInterface $form_state) {
     // Trim the submitted value of whitespace and slashes.
-    $alias = trim(trim($element['alias']['#value']), '/');
+    $alias = trim($element['alias']['#value'], " \t\n\r\0\x0B\\/");
     if (!empty($alias)) {
       $form_state->setValueForElement($element['alias'], $alias);
 
diff --git a/core/modules/path/src/Tests/PathAliasTest.php b/core/modules/path/src/Tests/PathAliasTest.php
index c61c6b6..f1dc2a5 100644
--- a/core/modules/path/src/Tests/PathAliasTest.php
+++ b/core/modules/path/src/Tests/PathAliasTest.php
@@ -150,7 +150,7 @@ function testAdminAlias() {
 
     // Create alias with trailing slash.
     $edit = array();
-    $edit['source'] = 'node/' . $node3->id();
+    $edit['source'] = 'node/' . $node4->id();
     $edit['alias'] = $this->randomMachineName(8) . '/';
     $this->drupalPostForm('admin/config/search/path/add', $edit, t('Save'));