diff --git a/README.md b/README.md
index 2d366c5..9a7b619 100644
--- a/README.md
+++ b/README.md
@@ -48,6 +48,7 @@ When comments are disabled, WP Baseline comprehensively removes all comment func
 - Redirects comment admin pages to dashboard
 - Removes comment link from admin bar
 - Disables comment REST API endpoints
+- Disables block editor notes (prevents `/wp/v2/comments?type=note` requests when the REST route is removed)
 
 **Frontend Changes:**
 - Disables comment feeds
diff --git a/inc/Comments/Actions.php b/inc/Comments/Actions.php
index 36253dd..074f9ca 100644
--- a/inc/Comments/Actions.php
+++ b/inc/Comments/Actions.php
@@ -25,15 +25,18 @@ public function init()
 			return;
 		}
 
-		// If init has already fired, run immediately
+		add_filter('register_post_type_args', [$this, 'strip_editor_notes_from_post_type_args'], 10, 2);
+		add_action('registered_post_type', [$this, 'disable_editor_notes_support'], 999, 2);
+
+		// Run late on init so post types registered after priority 0 are included.
 		if (did_action('init')) {
 			$this->disable_comments();
 			$this->disable_comment_feeds();
 		} else {
-			add_action('init', [$this, 'disable_comments']);
+			add_action('init', [$this, 'disable_comments'], 999);
 			add_action('init', [$this, 'disable_comment_feeds']);
 		}
-		
+
 		add_action('admin_menu', [$this, 'remove_dashboard_sections']);
 		add_action('wp_before_admin_bar_render', [$this, 'hide_admin_toolbar_link']);
 		add_action('widgets_init', [$this, 'disable_comment_widgets']);
@@ -55,6 +58,8 @@ public function disable_comments()
 				remove_post_type_support($post_type, 'comments');
 				remove_post_type_support($post_type, 'trackbacks');
 			}
+
+			$this->disable_editor_notes_support($post_type);
 		}
 
 		$wpdb = $GLOBALS['wpdb'];
@@ -68,6 +73,73 @@ public function disable_comments()
 		add_filter('pings_open', '__return_false', 20, 2);
 	}
 
+	/**
+	 * Strip editor notes from post type args before registration.
+	 *
+	 * @param array  $args      Post type registration arguments.
+	 * @param string $post_type Post type name.
+	 */
+	public function strip_editor_notes_from_post_type_args(array $args, string $post_type): array
+	{
+		if (empty($args['supports']) || !is_array($args['supports'])) {
+			return $args;
+		}
+
+		$supports = [];
+
+		foreach ($args['supports'] as $key => $value) {
+			if ('editor' === $key && is_array($value)) {
+				unset($value['notes']);
+				if ($value === []) {
+					$supports[] = 'editor';
+					continue;
+				}
+				$supports[$key] = $value;
+				continue;
+			}
+
+			if (is_int($key)) {
+				$supports[] = $value;
+				continue;
+			}
+
+			$supports[$key] = $value;
+		}
+
+		$args['supports'] = $supports;
+
+		return $args;
+	}
+
+	/**
+	 * Remove block editor notes support so the editor does not call the comments REST API.
+	 *
+	 * Core registers posts/pages with `editor => [ 'notes' => true ]`, which mounts the
+	 * collaboration sidebar and requests /wp/v2/comments?type=note even when discussion
+	 * comments are closed. That conflicts with disabled comment REST routes.
+	 */
+	public function disable_editor_notes_support(string $post_type): void
+	{
+		if (!post_type_supports($post_type, 'editor')) {
+			return;
+		}
+
+		$supports = get_all_post_type_supports($post_type);
+		$editor_support = $supports['editor'] ?? null;
+
+		if (!is_array($editor_support)) {
+			return;
+		}
+
+		foreach ($editor_support as $item) {
+			if (!empty($item['notes'])) {
+				remove_post_type_support($post_type, 'editor');
+				add_post_type_support($post_type, 'editor');
+				return;
+			}
+		}
+	}
+
 	/**
 	 * Remove the comments menu page and submenu page.
 	 */
diff --git a/inc/Security/Login.php b/inc/Security/Login.php
index 310b6e0..044498f 100644
--- a/inc/Security/Login.php
+++ b/inc/Security/Login.php
@@ -35,17 +35,29 @@ public function init()
 	 */
 	public function prevent_username_login($user, $username, $password)
 	{
-		if (!empty($username) && is_email($username)) {
+		// Let core handle empty credentials on initial GET (wp_signon runs before the form).
+		if ($username === '' || $username === null) {
 			return $user;
 		}
+
+		if (is_email($username)) {
+			return $user;
+		}
+
 		return new \WP_Error('invalid_email', __('Please use your email address to login.', 'wp-baseline'));
 	}
 
 	/**
-	 * Returns a generic login error message
+	 * Returns a generic login error message.
+	 *
+	 * @param string $errors HTML error messages from the login screen.
 	 */
-	public function generic_login_error()
+	public function generic_login_error($errors)
 	{
+		if ($errors === '') {
+			return $errors;
+		}
+
 		return __('The email address or password you entered is incorrect.', 'wp-baseline');
 	}