diff -u b/core/lib/Drupal/Core/Block/BlockOperationsProviderInterface.php b/core/lib/Drupal/Core/Block/BlockOperationsProviderInterface.php
--- b/core/lib/Drupal/Core/Block/BlockOperationsProviderInterface.php
+++ b/core/lib/Drupal/Core/Block/BlockOperationsProviderInterface.php
@@ -14,7 +14,7 @@
   /**
    * Returns a list of operation links available for this block.
    *
-   * @return array
+   * @return array[]
    *   An array of operation links. Keys in this array will overwrite keys of
    *   operations defined in
    *   \Drupal\block\BlockListBuilder::getDefaultOperations().
@@ -24,5 +24,5 @@
    *     - weight: The link weight.
    */
-  public function getOperationLinks();
+  public function getOperationLinks(): array;
 
 }
diff -u b/core/modules/block/src/BlockInterface.php b/core/modules/block/src/BlockInterface.php
--- b/core/modules/block/src/BlockInterface.php
+++ b/core/modules/block/src/BlockInterface.php
@@ -125,7 +125,7 @@
   /**
    * Returns a list of operation links available for this block.
    *
-   * @return array
+   * @return array[]
    *   An array of operation links. Keys in this array will overwrite keys of
    *   operations defined in
    *   \Drupal\block\BlockListBuilder::getDefaultOperations().
diff -u b/core/modules/block/src/BlockListBuilder.php b/core/modules/block/src/BlockListBuilder.php
--- b/core/modules/block/src/BlockListBuilder.php
+++ b/core/modules/block/src/BlockListBuilder.php
@@ -366,8 +366,11 @@
       $operations['delete']['title'] = $this->t('Remove');
     }
 
+    // Check for any additional operations. Example edit-view.
+    // Since these additional operations will take the user away from the
+    // block layout page, we add a destination parameter to redirect the user
+    // back.
     $operation_extras = $entity->getOperationLinks();
-
     foreach ($operation_extras as $key => $operation_extra) {
       if ($operation_extra['url']->getOption('query')) {
         $operation_extra['url']->mergeOptions([
diff -u b/core/modules/block_content/src/Plugin/Block/BlockContentBlock.php b/core/modules/block_content/src/Plugin/Block/BlockContentBlock.php
--- b/core/modules/block_content/src/Plugin/Block/BlockContentBlock.php
+++ b/core/modules/block_content/src/Plugin/Block/BlockContentBlock.php
@@ -217,17 +217,19 @@
   /**
    * {@inheritdoc}
    */
-  public function getOperationLinks() {
+  public function getOperationLinks(): array {
     $custom_block = $this->getEntity();
     $links = [];
 
-    // Check the current user has the appropriate permission to edit this
+    // Check that the current user has the appropriate permission to edit this
     // custom block.
     if ($custom_block->access('edit')) {
-      // Set url options to an empty array as the destination will be set later.
       $links['block-edit'] = [
         'title' => $this->t('Edit block'),
+        // Set URL options to an empty array as the destination will be set
+        // later in \Drupal\block\BlockListBuilder.
         'url' => $custom_block->toUrl('edit-form')->setOptions([]),
+        // Using this weight so this option appears at the top.
         'weight' => 50,
       ];
     }
diff -u b/core/modules/block_content/tests/src/Kernel/BlockContentTest.php b/core/modules/block_content/tests/src/Kernel/BlockContentTest.php
--- b/core/modules/block_content/tests/src/Kernel/BlockContentTest.php
+++ b/core/modules/block_content/tests/src/Kernel/BlockContentTest.php
@@ -41,7 +41,7 @@
     $block_content_type = BlockContentType::create([
       'id' => 'spiffy',
       'label' => 'Mucho spiffy',
-      'description' => "Provides a block type that increases your site's spiffiness by upto 11%",
+      'description' => "Provides a block type that increases your site's spiffiness by up to 11%",
     ]);
     $block_content_type->save();
     // And a block content entity.
@@ -64,12 +64,14 @@
       'weight' => 50,
     ];
 
-    // Test when user doesn't have "administer block" permission.
+    // At this point, we are logged in as anonymous, so the user doesn't
+    // have the "administer block" permission.
     $this->assertEmpty($links);
 
     $this->setUpCurrentUser(['uid' => 1], ['edit any spiffy block content']);
     $links = $block->getOperationLinks();
-    // Test when user does have "administer block" permission.
+    // At this point, we are logged in as an admin, so the user does
+    // have the "administer block" permission.
     $this->assertEquals(['block-edit' => $block_link], $links);
   }
 
diff -u b/core/modules/system/src/Plugin/Block/SystemMenuBlock.php b/core/modules/system/src/Plugin/Block/SystemMenuBlock.php
--- b/core/modules/system/src/Plugin/Block/SystemMenuBlock.php
+++ b/core/modules/system/src/Plugin/Block/SystemMenuBlock.php
@@ -50,14 +50,14 @@
    *
    * @var \Drupal\Core\Extension\ModuleHandlerInterface
    */
-  protected $moduleHandler;
+  protected ModuleHandlerInterface $moduleHandler;
 
   /**
    * The current user.
    *
    * @var \Drupal\Core\Session\AccountInterface
    */
-  protected $user;
+  protected AccountInterface $user;
 
   /**
    * Constructs a new SystemMenuBlock.
@@ -72,13 +72,22 @@
    *   The menu tree service.
    * @param \Drupal\Core\Menu\MenuActiveTrailInterface $menu_active_trail
    *   The active menu trail service.
-   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface|null $module_handler
    *   The module handler used to check whether menu_ui is installed.
-   * @param \Drupal\Core\Session\AccountInterface $user
+   * @param \Drupal\Core\Session\AccountInterface|null $user
    *   The current user.
    */
-  public function __construct(array $configuration, $plugin_id, $plugin_definition, MenuLinkTreeInterface $menu_tree, MenuActiveTrailInterface $menu_active_trail, ModuleHandlerInterface $module_handler, AccountInterface $user) {
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, MenuLinkTreeInterface $menu_tree, MenuActiveTrailInterface $menu_active_trail, ModuleHandlerInterface $module_handler = NULL, AccountInterface $user = NULL) {
     parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    if (is_null($module_handler)) {
+      @trigger_error('The SystemMenuBlock constructor now accepts \Drupal\Core\Extension\ModuleHandlerInterface in drupal:10.1.0 and is required in drupal:11.0.0. See https://www.drupal.org/node/3333923.', E_USER_DEPRECATED);
+    }
+
+    if (is_null($user)) {
+      @trigger_error('The SystemMenuBlock constructor now accepts \Drupal\Core\Session\AccountInterface in drupal:10.1.0 and is required in drupal:11.0.0. See https://www.drupal.org/node/3333923.', E_USER_DEPRECATED);
+    }
+
     $this->menuTree = $menu_tree;
     $this->menuActiveTrail = $menu_active_trail;
     $this->moduleHandler = $module_handler;
@@ -262,7 +271,7 @@
   /**
    * {@inheritdoc}
    */
-  public function getOperationLinks() {
+  public function getOperationLinks(): array {
     $menu_name = $this->getDerivativeId();
 
     $links = [];
diff -u b/core/modules/system/tests/src/Kernel/Block/SystemMenuBlockTest.php b/core/modules/system/tests/src/Kernel/Block/SystemMenuBlockTest.php
--- b/core/modules/system/tests/src/Kernel/Block/SystemMenuBlockTest.php
+++ b/core/modules/system/tests/src/Kernel/Block/SystemMenuBlockTest.php
@@ -155,7 +155,7 @@
     $block = Block::create([
       'plugin' => 'system_menu_block:' . $this->menu->id(),
       'region' => 'footer',
-      'id' => 'machinename',
+      'id' => 'machine_name',
       'theme' => 'stark',
     ]);
 
@@ -181,7 +181,7 @@
     $block = Block::create([
       'plugin' => 'system_menu_block:' . $this->menu->id(),
       'region' => 'footer',
-      'id' => 'machinename',
+      'id' => 'machine_name',
       'theme' => 'stark',
     ]);
 
@@ -209,7 +209,7 @@
     $place_block = function ($level, $depth) {
       return $this->blockManager->createInstance('system_menu_block:' . $this->menu->id(), [
         'region' => 'footer',
-        'id' => 'machinename',
+        'id' => 'machine_name',
         'theme' => 'stark',
         'level' => $level,
         'depth' => $depth,
@@ -317,7 +317,7 @@
   public function testConfigExpanded($active_route, $menu_block_level, $expected_items) {
     $block = $this->blockManager->createInstance('system_menu_block:' . $this->menu->id(), [
       'region' => 'footer',
-      'id' => 'machinename',
+      'id' => 'machine_name',
       'theme' => 'stark',
       'level' => $menu_block_level,
       'depth' => 0,
diff -u b/core/modules/views/src/Plugin/Block/ViewsBlockBase.php b/core/modules/views/src/Plugin/Block/ViewsBlockBase.php
--- b/core/modules/views/src/Plugin/Block/ViewsBlockBase.php
+++ b/core/modules/views/src/Plugin/Block/ViewsBlockBase.php
@@ -249,7 +249,7 @@
   /**
    * {@inheritdoc}
    */
-  public function getOperationLinks() {
+  public function getOperationLinks(): array {
     $view = $this->view;
     $display_id = $this->displayID;
     $links = [];
diff -u b/core/modules/views/tests/src/Kernel/Plugin/ViewsBlockTest.php b/core/modules/views/tests/src/Kernel/Plugin/ViewsBlockTest.php
--- b/core/modules/views/tests/src/Kernel/Plugin/ViewsBlockTest.php
+++ b/core/modules/views/tests/src/Kernel/Plugin/ViewsBlockTest.php
@@ -170,13 +170,15 @@
       'weight' => 50,
     ];
 
-    // Test when user doesn't have "administer views" permission.
+    // At this point, we are logged in as anonymous, so the user doesn't
+    // have the "administer views" permission.
     $this->assertEmpty($links);
 
     $this->setUpCurrentUser(['uid' => 1], ['administer views']);
 
     $links = $block->getOperationLinks();
-    // Test when user does have "administer views" permission.
+    // At this point, we are logged in as an admin, so the user does
+    // have the "administer views" permission.
     $this->assertEquals(['view-edit' => $view_link], $links);
   }