diff --git a/core/modules/block/src/Tests/BlockLanguageCacheTest.php b/core/modules/block/src/Tests/BlockLanguageCacheTest.php
index 543e65e..a11bdd6 100644
--- a/core/modules/block/src/Tests/BlockLanguageCacheTest.php
+++ b/core/modules/block/src/Tests/BlockLanguageCacheTest.php
@@ -62,7 +62,7 @@ public function testBlockLinks() {
     // Create the block cache for all languages.
     foreach ($this->langcodes as $langcode) {
       $this->drupalGet('admin/structure/block', array('language' => $langcode));
-      $this->clickLink('Place block');
+      $this->clickLinkPartialName('Place block');
     }
 
     // Create a menu in the default language.
@@ -74,7 +74,7 @@ public function testBlockLinks() {
     // Check that the block is listed for all languages.
     foreach ($this->langcodes as $langcode) {
       $this->drupalGet('admin/structure/block', array('language' => $langcode));
-      $this->clickLink('Place block');
+      $this->clickLinkPartialName('Place block');
       $this->assertText($edit['label']);
     }
   }
diff --git a/core/modules/block/src/Tests/BlockUiTest.php b/core/modules/block/src/Tests/BlockUiTest.php
index 1f26739..37fce6e 100644
--- a/core/modules/block/src/Tests/BlockUiTest.php
+++ b/core/modules/block/src/Tests/BlockUiTest.php
@@ -146,7 +146,7 @@ public function testCandidateBlockList() {
     $pattern = '//tr[.//td/div[text()=:title] and .//td[text()=:category] and .//td//a[contains(@href, :href)]]';
 
     $this->drupalGet('admin/structure/block');
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $elements = $this->xpath($pattern, $arguments);
     $this->assertTrue(!empty($elements), 'The test block appears in the category for its module.');
 
@@ -155,7 +155,7 @@ public function testCandidateBlockList() {
     $this->container->get('plugin.manager.block')->clearCachedDefinitions();
 
     $this->drupalGet('admin/structure/block');
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $arguments[':category'] = 'Custom category';
     $elements = $this->xpath($pattern, $arguments);
     $this->assertTrue(!empty($elements), 'The test block appears in a custom category controlled by block_test_block_alter().');
diff --git a/core/modules/block/src/Tests/BlockXssTest.php b/core/modules/block/src/Tests/BlockXssTest.php
index 0baa67f..3d9bfd3 100644
--- a/core/modules/block/src/Tests/BlockXssTest.php
+++ b/core/modules/block/src/Tests/BlockXssTest.php
@@ -51,7 +51,7 @@ public function testXssInCategory() {
     $this->drupalPlaceBlock('test_xss_title');
     $this->drupalLogin($this->drupalCreateUser(['administer blocks', 'access administration pages']));
     $this->drupalGet(Url::fromRoute('block.admin_display'));
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $this->assertNoRaw("<script>alert('XSS category');</script>");
   }
 
@@ -78,7 +78,7 @@ protected function doViewTest() {
     $view->save();
 
     $this->drupalGet(Url::fromRoute('block.admin_display'));
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     // The block admin label is automatically XSS admin filtered.
     $this->assertRaw('alert("view");');
     $this->assertNoRaw('<script>alert("view");</script>');
@@ -94,7 +94,7 @@ protected function doMenuTest() {
     ])->save();
 
     $this->drupalGet(Url::fromRoute('block.admin_display'));
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     // The block admin label is automatically XSS admin filtered.
     $this->assertRaw('alert("menu");');
     $this->assertNoRaw('<script>alert("menu");</script>');
@@ -115,7 +115,7 @@ protected function doBlockContentTest() {
     ])->save();
 
     $this->drupalGet(Url::fromRoute('block.admin_display'));
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     // The block admin label is automatically XSS admin filtered.
     $this->assertRaw('alert("block_content");');
     $this->assertNoRaw('<script>alert("block_content");</script>');
diff --git a/core/modules/block/src/Tests/Views/DisplayBlockTest.php b/core/modules/block/src/Tests/Views/DisplayBlockTest.php
index d9f9196..880f68c 100644
--- a/core/modules/block/src/Tests/Views/DisplayBlockTest.php
+++ b/core/modules/block/src/Tests/Views/DisplayBlockTest.php
@@ -70,7 +70,7 @@ public function testBlockCategory() {
       ':category' => t('Lists (Views)'),
     );
     $this->drupalGet('admin/structure/block');
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $elements = $this->xpath($pattern, $arguments);
     $this->assertTrue(!empty($elements), 'The test block appears in the category for its base table.');
 
@@ -95,7 +95,7 @@ public function testBlockCategory() {
     // Test that the blocks are listed under the correct categories.
     $arguments[':category'] = $category;
     $this->drupalGet('admin/structure/block');
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $elements = $this->xpath($pattern, $arguments);
     $this->assertTrue(!empty($elements), 'The test block appears in the custom category.');
 
diff --git a/core/modules/block_content/src/Tests/BlockContentTypeTest.php b/core/modules/block_content/src/Tests/BlockContentTypeTest.php
index 681c6ce..20dc1a2 100644
--- a/core/modules/block_content/src/Tests/BlockContentTypeTest.php
+++ b/core/modules/block_content/src/Tests/BlockContentTypeTest.php
@@ -189,7 +189,7 @@ public function testsBlockContentAddTypes() {
         // block configure form.
         $path = $theme == $default_theme ? 'admin/structure/block' : "admin/structure/block/list/$theme";
         $this->drupalGet($path);
-        $this->clickLink('Place block');
+        $this->clickLinkPartialName('Place block');
         $this->clickLink(t('Add custom block'));
         // The seven theme has markup inside the link, we cannot use clickLink().
         if ($default_theme == 'seven') {
diff --git a/core/modules/menu_ui/src/Tests/MenuTest.php b/core/modules/menu_ui/src/Tests/MenuTest.php
index 3c00e92..34dacc5 100644
--- a/core/modules/menu_ui/src/Tests/MenuTest.php
+++ b/core/modules/menu_ui/src/Tests/MenuTest.php
@@ -219,7 +219,7 @@ function addCustomMenu() {
 
     // Confirm that the custom menu block is available.
     $this->drupalGet('admin/structure/block/list/' . $this->config('system.theme')->get('default'));
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $this->assertText($label);
 
     // Enable the block.
@@ -533,7 +533,7 @@ function testSystemMenuRename() {
     // Make sure menu shows up with new name in block addition.
     $default_theme = $this->config('system.theme')->get('default');
     $this->drupalget('admin/structure/block/list/' . $default_theme);
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $this->assertText($edit['label']);
   }
 
diff --git a/core/modules/search/src/Tests/SearchBlockTest.php b/core/modules/search/src/Tests/SearchBlockTest.php
index 2348ae0..4b774a1 100644
--- a/core/modules/search/src/Tests/SearchBlockTest.php
+++ b/core/modules/search/src/Tests/SearchBlockTest.php
@@ -36,7 +36,7 @@ public function testSearchFormBlock() {
 
     // Test availability of the search block in the admin "Place blocks" list.
     $this->drupalGet('admin/structure/block');
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $this->assertLinkByHref('/admin/structure/block/add/search_form_block/classy', 0,
       'Did not find the search block in block candidate list.');
 
diff --git a/core/modules/simpletest/src/WebTestBase.php b/core/modules/simpletest/src/WebTestBase.php
index e17d703..c43888b 100644
--- a/core/modules/simpletest/src/WebTestBase.php
+++ b/core/modules/simpletest/src/WebTestBase.php
@@ -2324,7 +2324,7 @@ protected function handleForm(&$post, &$edit, &$upload, $submit, $form) {
   }
 
   /**
-   * Follows a link by name.
+   * Follows a link by complete name.
    *
    * Will click the first link found with this link text by default, or a later
    * one if an index is given. Match is case sensitive with normalized space.
@@ -2332,17 +2332,54 @@ protected function handleForm(&$post, &$edit, &$upload, $submit, $form) {
    *
    * If the link is discovered and clicked, the test passes. Fail otherwise.
    *
-   * @param $label
+   * @param string $label
    *   Text between the anchor tags.
-   * @param $index
+   * @param int $index
    *   Link position counting from zero.
    *
-   * @return
+   * @return string|bool
    *   Page contents on success, or FALSE on failure.
    */
   protected function clickLink($label, $index = 0) {
+    return $this->clickLinkHelper($label, $index, '//a[normalize-space()=:label]');
+  }
+
+  /**
+   * Follows a link by partial name.
+   *
+   *
+   * If the link is discovered and clicked, the test passes. Fail otherwise.
+   *
+   * @param string $label
+   *   Text between the anchor tags, uses starts-with().
+   * @param int $index
+   *   Link position counting from zero.
+   *
+   * @return string|bool
+   *   Page contents on success, or FALSE on failure.
+   *
+   * @see ::clickLink()
+   */
+  protected function clickLinkPartialName($label, $index = 0) {
+    return $this->clickLinkHelper($label, $index, '//a[starts-with(normalize-space(), :label)]');
+  }
+
+  /**
+   * Provides a helper for ::clickLink() and ::clickLinkPartialName().
+   *
+   * @param string $label
+   *   Text between the anchor tags, uses starts-with().
+   * @param int $index
+   *   Link position counting from zero.
+   * @param string $pattern
+   *   A pattern to use for the XPath.
+   *
+   * @return bool|string
+   *   Page contents on success, or FALSE on failure.
+   */
+  protected function clickLinkHelper($label, $index, $pattern) {
     $url_before = $this->getUrl();
-    $urls = $this->xpath('//a[normalize-space()=:label]', array(':label' => $label));
+    $urls = $this->xpath($pattern, array(':label' => $label));
     if (isset($urls[$index])) {
       $url_target = $this->getAbsoluteUrl($urls[$index]['href']);
       $this->pass(SafeMarkup::format('Clicked link %label (@url_target) from @url_before', array('%label' => $label, '@url_target' => $url_target, '@url_before' => $url_before)), 'Browser');
diff --git a/core/modules/views/src/Tests/Wizard/BasicTest.php b/core/modules/views/src/Tests/Wizard/BasicTest.php
index 2ba0dac..fe736de 100644
--- a/core/modules/views/src/Tests/Wizard/BasicTest.php
+++ b/core/modules/views/src/Tests/Wizard/BasicTest.php
@@ -133,7 +133,7 @@ function testViewsWizardAndListing() {
 
     // Confirm that the block is available in the block administration UI.
     $this->drupalGet('admin/structure/block/list/' . $this->config('system.theme')->get('default'));
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $this->assertText($view3['label']);
 
     // Place the block.
diff --git a/core/modules/views/src/Tests/Wizard/ItemsPerPageTest.php b/core/modules/views/src/Tests/Wizard/ItemsPerPageTest.php
index 7fd06d0..132df58 100644
--- a/core/modules/views/src/Tests/Wizard/ItemsPerPageTest.php
+++ b/core/modules/views/src/Tests/Wizard/ItemsPerPageTest.php
@@ -71,7 +71,7 @@ function testItemsPerPage() {
 
     // Confirm that the block is listed in the block administration UI.
     $this->drupalGet('admin/structure/block/list/' . $this->config('system.theme')->get('default'));
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $this->assertText($view['label']);
 
     // Place the block, visit a page that displays the block, and check that the
diff --git a/core/modules/views_ui/src/Tests/OverrideDisplaysTest.php b/core/modules/views_ui/src/Tests/OverrideDisplaysTest.php
index 15b6c88..2a693f7 100644
--- a/core/modules/views_ui/src/Tests/OverrideDisplaysTest.php
+++ b/core/modules/views_ui/src/Tests/OverrideDisplaysTest.php
@@ -50,7 +50,7 @@ function testOverrideDisplays() {
 
     // Confirm that the view block is available in the block administration UI.
     $this->drupalGet('admin/structure/block/list/' . $this->config('system.theme')->get('default'));
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $this->assertText($view['label']);
 
     // Place the block.
@@ -110,7 +110,7 @@ function testWizardMixedDefaultOverriddenDisplays() {
 
     // Confirm that the block is available in the block administration UI.
     $this->drupalGet('admin/structure/block/list/' . $this->config('system.theme')->get('default'));
-    $this->clickLink('Place block');
+    $this->clickLinkPartialName('Place block');
     $this->assertText($view['label']);
 
     // Put the block into the first sidebar region, and make sure it will not