diff --git a/src/js/_enqueues/admin/postbox.js b/src/js/_enqueues/admin/postbox.js
index fec46d3f6d909..3b103a44a0441 100644
--- a/src/js/_enqueues/admin/postbox.js
+++ b/src/js/_enqueues/admin/postbox.js
@@ -355,6 +355,21 @@
 				postboxes.setMetaBoxReordering( enabled );
 				postboxes.save_meta_box_reordering_state( enabled );
 			} );
+
+			$( '.wp-on-this-day-toggle' ).on( 'click.postboxes', function() {
+				var enabled = $( this ).prop( 'checked' );
+
+				postboxes.setOnThisDayDisplay( enabled );
+				postboxes.save_on_this_day_display( enabled );
+			} );
+
+			$( '#wp-on-this-day-posts-form button' ).on( 'click.postboxes', function( event ) {
+				event.preventDefault();
+				var enabled = '1' === $( this ).prop( 'value' );
+
+				postboxes.setOnThisDayDisplay( enabled );
+				postboxes.save_on_this_day_display( enabled );
+			} );
 		},
 
 		/**
@@ -495,6 +510,26 @@
 			}
 		},
 
+		/**
+		 * Enables or disables the On This Day display in the activity widget.
+		 *
+		 * @since 7.2.0
+		 *
+		 * @param {boolean} enabled Whether On This Day should be enabled.
+		 * @return {void}
+		 */
+		setOnThisDayDisplay: function( enabled ) {
+			var $onThisDayWidget = $( '#wp-on-this-day-posts' ),
+				$onThisDayList = $( '#wp-on-this-day-posts-list' ),
+				$onThisDayForm = $( '#wp-on-this-day-posts-form'),
+				$onThisDayScreenOption = $( '#wp-on-this-day-toggle' );
+
+			$onThisDayForm.hide(); // Always hidden once a choice is made.
+			$onThisDayWidget.toggle( enabled ).toggleClass( 'hidden', ! enabled );
+			$onThisDayList.toggle( enabled );
+			$onThisDayScreenOption.prop( 'checked', enabled );
+		},
+
 		/**
 		 * Saves the state of the postboxes to the server.
 		 *
@@ -560,6 +595,32 @@
 			);
 		},
 
+		/**
+		 * Saves the On This Day setting to the server.
+		 *
+		 * @since 7.2.0
+		 *
+		 * @param {boolean} enabled Whether On This Day activity is enabled.
+		 * @return {void}
+		 */
+		save_on_this_day_display: function( enabled ) {
+			$.post(
+				ajaxurl,
+				{
+					action: 'on-this-day-display',
+					enabled: enabled ? 1 : 0,
+					screenoptionnonce: $( '#screenoptionnonce' ).val()
+				},
+				function() {
+					wp.a11y.speak(
+						enabled ?
+							__( 'On This Day display is enabled.' ) :
+							__( 'On This Day display is disabled.' )
+					);
+				}
+			);
+		},
+
 		/**
 		 * Saves the order of the postboxes to the server.
 		 *
diff --git a/src/wp-admin/admin-ajax.php b/src/wp-admin/admin-ajax.php
index e62c285fa356c..0472c3bea45b8 100644
--- a/src/wp-admin/admin-ajax.php
+++ b/src/wp-admin/admin-ajax.php
@@ -79,6 +79,7 @@
 	'closed-postboxes',
 	'hidden-columns',
 	'meta-box-reordering',
+	'on-this-day-display',
 	'update-welcome-panel',
 	'menu-get-metabox',
 	'wp-link-ajax',
diff --git a/src/wp-admin/css/dashboard.css b/src/wp-admin/css/dashboard.css
index a79960cb39419..547251e8959b1 100644
--- a/src/wp-admin/css/dashboard.css
+++ b/src/wp-admin/css/dashboard.css
@@ -931,27 +931,28 @@ body #dashboard-widgets .postbox form .submit {
 
 #future-posts ul,
 #published-posts ul,
-#on-this-day-posts ul {
+#wp-on-this-day-posts ul {
 	margin: 8px -12px 0 -12px;
 }
 
 #future-posts li,
 #published-posts li,
-#on-this-day-posts li {
+#wp-on-this-day-posts li {
 	display: grid;
 	grid-template-columns: clamp(160px, calc(2vw + 140px), 200px) auto;
 	column-gap: 10px;
 	color: #646970;
-	padding: 4px 12px;
+	padding: 7px 12px;
+	margin-bottom: 0;
 }
 
 #future-posts li:nth-child(odd),
 #published-posts li:nth-child(odd),
-#on-this-day-posts li:nth-child(odd) {
+#wp-on-this-day-posts-list li:nth-child(odd) {
 	background-color: #f6f7f7;
 }
 
-#on-this-day-posts .wp-on-this-day-post-author {
+#wp-on-this-day-posts-list .wp-on-this-day-post-author {
 	color: #646970;
 }
 
@@ -966,6 +967,13 @@ body #dashboard-widgets .postbox form .submit {
 	margin-bottom: 0;
 }
 
+/* The last visible block, ignoring any hidden blocks that follow it. */
+.activity-block:nth-last-child(1 of :not(.hidden)),
+.no-js .activity-block:nth-last-child(1 of :not(.hidden, .hide-if-no-js)) {
+	border-bottom: none;
+	margin-bottom: 0;
+}
+
 .activity-block .subsubsub li {
 	color: #646970;
 }
diff --git a/src/wp-admin/includes/ajax-actions.php b/src/wp-admin/includes/ajax-actions.php
index 03fefef0689ff..4a335d374ecd6 100644
--- a/src/wp-admin/includes/ajax-actions.php
+++ b/src/wp-admin/includes/ajax-actions.php
@@ -1818,6 +1818,22 @@ function wp_ajax_meta_box_reordering() {
 	wp_die( 1 );
 }
 
+/**
+ * Handles the On This Day display setting via Ajax.
+ *
+ * @since 7.2.0
+ *
+ * @return never
+ */
+function wp_ajax_on_this_day_display(): void {
+	check_ajax_referer( 'screen-options-nonce', 'screenoptionnonce' );
+
+	$enabled = isset( $_POST['enabled'] ) && is_string( $_POST['enabled'] ) && '1' === $_POST['enabled'];
+	update_user_option( get_current_user_id(), 'dashboard_show_on_this_day', $enabled ? 'opt-in' : 'opt-out' );
+
+	wp_die( 1 );
+}
+
 /**
  * Handles updating whether to display the welcome panel via AJAX.
  *
diff --git a/src/wp-admin/includes/class-wp-screen.php b/src/wp-admin/includes/class-wp-screen.php
index 0008130355efb..be3ba6ae556bf 100644
--- a/src/wp-admin/includes/class-wp-screen.php
+++ b/src/wp-admin/includes/class-wp-screen.php
@@ -1011,6 +1011,7 @@ public function show_screen_options() {
 
 		if ( $has_meta_boxes ) {
 			$additional_settings .= $this->get_meta_box_reordering_option();
+			$additional_settings .= $this->get_on_this_day_option();
 		}
 
 		if ( 'post' === $this->base ) {
@@ -1184,6 +1185,18 @@ private function get_meta_box_reordering_option() {
 			. '<label for="meta-box-reordering">' . __( 'Allow screen elements to be rearranged' ) . '</label>';
 	}
 
+	/**
+	 * Gets the option to enable or disable meta box reordering.
+	 *
+	 * @since 7.2.0
+	 *
+	 * @return string Meta box reordering option markup.
+	 */
+	private function get_on_this_day_option(): string {
+		return '<input class="wp-on-this-day-toggle" name="wp-on-this-day-toggle" type="checkbox" id="wp-on-this-day-toggle" value="opt-in"' . checked( wp_is_on_this_day_enabled(), true, false ) . ' />'
+			. '<label for="wp-on-this-day-toggle">' . __( 'Display "On This Day" posts in Activity' ) . '</label>';
+	}
+
 	/**
 	 * Checks whether the screen has meta boxes.
 	 *
diff --git a/src/wp-admin/includes/dashboard.php b/src/wp-admin/includes/dashboard.php
index 165b556f9eb85..ee2a6ef5e6fc5 100644
--- a/src/wp-admin/includes/dashboard.php
+++ b/src/wp-admin/includes/dashboard.php
@@ -1020,6 +1020,25 @@ function wp_dashboard_site_activity() {
  * @return bool False if no posts were found. True otherwise.
  */
 function wp_dashboard_on_this_day( $posts = null ) {
+	if ( 'opt-out' === get_user_option( 'dashboard_show_on_this_day' ) ) {
+		$display_list = false;
+		$display_form = false;
+	} elseif ( 'opt-in' === get_user_option( 'dashboard_show_on_this_day' ) ) {
+		$display_list = true;
+		$display_form = false;
+	} else {
+		/*
+		 * User has not yet chosen to opt-in or -out.
+		 *
+		 * As On This Day features can be distressing in some circumstances,
+		 * users are prompted to opt-in or -out of the feature prior to the
+		 * list of posts being displayed. If they have done neither a form is
+		 * displayed prompting them to make a choice.
+		 */
+		$display_list = false;
+		$display_form = true;
+	}
+
 	if ( null === $posts ) {
 		$posts = wp_dashboard_on_this_day_get_posts();
 	}
@@ -1028,9 +1047,29 @@ function wp_dashboard_on_this_day( $posts = null ) {
 		return false;
 	}
 
-	echo '<div id="on-this-day-posts" class="activity-block">';
-	echo '<h3>' . esc_html__( 'Published On This Day' ) . '</h3>';
-	echo '<ul>';
+	?>
+	<div id="wp-on-this-day-posts" class="activity-block wp-on-this-day-posts-title <?php echo $display_form ? 'hide-if-no-js' : ''; ?> <?php echo ! $display_form && ! $display_list ? 'hidden' : ''; ?>">
+		<h3><?php _e( 'Published On This Day' ); ?></h3>
+	<?php
+
+	if ( $display_form ) :
+		?>
+		<form method="post" id="wp-on-this-day-posts-form">
+		<p>
+			<?php _e( 'Would you like to see posts from previous years here? You can change this later in the Screen Options tab.' ); ?>
+		</p>
+		<p>
+			<?php wp_nonce_field( 'screen-options-nonce', 'screenoptionnonce' ); ?>
+			<button name="enabled" value="1" class="button button-primary"><?php _e( 'Yes' ); ?></button>
+			<button name="enabled" value="0" class="button"><?php _e( 'No' ); ?></button>
+		</p>
+		</form>
+		<?php
+	endif;
+
+	?>
+	<ul id="wp-on-this-day-posts-list" <?php echo $display_list ? '' : 'class="hidden"'; ?>>
+	<?php
 
 	foreach ( $posts as $post ) {
 		/* translators: Date format for posts published in a previous year. */
@@ -1106,13 +1145,32 @@ function wp_dashboard_on_this_day( $posts = null ) {
  * @return WP_Post[] Array of posts ordered by newest first.
  */
 function wp_dashboard_on_this_day_get_posts() {
+	/**
+	 * Filters whether to short-circuit performing the query for the On This Day dashboard query.
+	 *
+	 * Filter to allow the bypassing of the SQL query for the On This Day section of the activity
+	 * widget.
+	 *
+	 * Return null for the default query to run or an array of post IDs to override the built in
+	 * database query. Returning an empty array will have the effect of turning the feature off.
+	 *
+	 * @since 7.2.0
+	 *
+	 * @param WP_Post[]|null $preflight Null to continue, array of post objects to bypass query.
+	 */
+	$preflight = apply_filters( 'pre_wp_dashboard_on_this_day_get_posts', null );
+
+	if ( is_array( $preflight ) ) {
+		return $preflight;
+	}
+
 	$today = current_datetime();
 	$year  = (int) $today->format( 'Y' );
 
 	$args = array(
 		'post_type'              => 'post',
 		'post_status'            => array( 'publish' ),
-		'posts_per_page'         => 10,
+		'posts_per_page'         => 100,
 		'ignore_sticky_posts'    => true,
 		'orderby'                => 'date',
 		'order'                  => 'DESC',
diff --git a/src/wp-admin/includes/screen.php b/src/wp-admin/includes/screen.php
index 3781aacdd1fa6..f529d361ad1e4 100644
--- a/src/wp-admin/includes/screen.php
+++ b/src/wp-admin/includes/screen.php
@@ -207,6 +207,19 @@ function wp_is_meta_box_reordering_enabled() {
 	return false === $setting ? true : 'disabled' !== $setting;
 }
 
+/**
+ * Determines whether On This Day display is enabled.
+ *
+ * @since 7.2.0
+ *
+ * @return bool Whether meta box reordering is enabled.
+ */
+function wp_is_on_this_day_enabled(): bool {
+	$setting = get_user_option( 'dashboard_show_on_this_day' );
+
+	return 'opt-in' === $setting;
+}
+
 /**
  * Register and configure an admin screen option
  *
diff --git a/tests/phpunit/tests/admin/wpDashboardSiteActivity.php b/tests/phpunit/tests/admin/wpDashboardSiteActivity.php
index 9d5f673afc7d6..8941b9d45c263 100644
--- a/tests/phpunit/tests/admin/wpDashboardSiteActivity.php
+++ b/tests/phpunit/tests/admin/wpDashboardSiteActivity.php
@@ -80,11 +80,13 @@ private function create_matching_post( $author_id, $title = 'A memory from last
 	}
 
 	/**
+	 * Tests that February 28 includes leap day posts in non-leap years.
+	 *
 	 * @ticket 65116
 	 *
 	 * @covers ::_wp_dashboard_on_this_day_date_query_clause
 	 */
-	public function test_date_query_includes_february_29_on_february_28_in_non_leap_year() {
+	public function test_otd_date_query_includes_february_29_on_february_28_in_non_leap_year() {
 		$date = new DateTimeImmutable( '2023-02-28 12:00:00', wp_timezone() );
 
 		$this->assertSame(
@@ -104,11 +106,13 @@ public function test_date_query_includes_february_29_on_february_28_in_non_leap_
 	}
 
 	/**
+	 * Tests that only published posts from this day in prior years are queried.
+	 *
 	 * @ticket 65116
 	 *
 	 * @covers ::wp_dashboard_on_this_day_get_posts
 	 */
-	public function test_query_returns_only_published_posts_from_this_day_in_previous_years() {
+	public function test_otd_query_returns_only_published_posts_from_this_day_in_previous_years() {
 		$matching_id = $this->create_matching_post( self::$user_id );
 		$this->create_matching_post( self::$user_id, 'A draft memory', 2, array( 'post_status' => 'draft' ) );
 
@@ -139,31 +143,54 @@ public function test_query_returns_only_published_posts_from_this_day_in_previou
 	}
 
 	/**
+	 * Tests that the On This Day query limit defaults to 100 and is filterable.
+	 *
 	 * @ticket 65116
 	 *
 	 * @covers ::wp_dashboard_on_this_day_get_posts
 	 */
-	public function test_query_defaults_to_ten_posts_and_limit_is_filterable() {
+	public function test_otd_query_defaults_to_one_hundred_posts_and_limit_is_filterable() {
 		for ( $years_ago = 1; $years_ago <= 11; $years_ago++ ) {
 			$this->create_matching_post( self::$user_id, 'Anniversary post ' . $years_ago, $years_ago );
 		}
 
-		$this->assertCount( 10, wp_dashboard_on_this_day_get_posts() );
+		$mock = new MockAction();
+		add_filter(
+			'wp_dashboard_on_this_day_query_args',
+			array( $mock, 'filter' ),
+			20 // Run after other filters have run.
+		);
 
-		add_filter( 'wp_dashboard_on_this_day_query_args', array( $this, 'filter_on_this_day_query_limit' ) );
-		try {
-			$this->assertCount( 3, wp_dashboard_on_this_day_get_posts() );
-		} finally {
-			remove_filter( 'wp_dashboard_on_this_day_query_args', array( $this, 'filter_on_this_day_query_limit' ) );
-		}
+		wp_dashboard_on_this_day_get_posts();
+		$this->assertCount( 11, wp_dashboard_on_this_day_get_posts(), 'Unfiltered OTD Widget should return all posts.' );
+		$this->assertSame( 2, $mock->get_call_count() );
+		$query_args = $mock->get_args()[ $mock->get_call_count() - 1 ][0];
+		$this->assertIsArray( $query_args );
+		$this->assertArrayHasKey( 'posts_per_page', $query_args );
+		$this->assertSame( 100, $query_args['posts_per_page'], 'OTD Widget query should default to 100 posts per page.' );
+
+		add_filter(
+			'wp_dashboard_on_this_day_query_args',
+			static function ( array $args ) {
+				$args['posts_per_page'] = 3;
+				return $args;
+			}
+		);
+		$this->assertCount( 3, wp_dashboard_on_this_day_get_posts(), 'Filtered OTD Widget should return three posts.' );
+		$query_args = $mock->get_args()[ $mock->get_call_count() - 1 ][0];
+		$this->assertIsArray( $query_args );
+		$this->assertArrayHasKey( 'posts_per_page', $query_args );
+		$this->assertSame( 3, $query_args['posts_per_page'], 'Filtered OTD Widget query should be limited to three posts per page.' );
 	}
 
 	/**
+	 * Tests that posts by all authors and untitled post excerpts are rendered.
+	 *
 	 * @ticket 65116
 	 *
 	 * @covers ::wp_dashboard_on_this_day
 	 */
-	public function test_section_renders_posts_from_all_authors_and_untitled_excerpts() {
+	public function test_otd_renders_posts_from_all_authors_and_untitled_excerpts() {
 		$this->create_matching_post( self::$user_id, 'A note from me' );
 		$this->create_matching_post( self::$other_user_id, 'A note from someone else', 2 );
 		$this->create_matching_post(
@@ -176,24 +203,27 @@ public function test_section_renders_posts_from_all_authors_and_untitled_excerpt
 		ob_start();
 		$result = wp_dashboard_on_this_day();
 		$output = ob_get_clean();
-
-		$this->assertTrue( $result );
-		$this->assertStringContainsString( 'Published On This Day', $output );
-		$this->assertStringContainsString( 'A note from me', $output );
-		$this->assertStringNotContainsString( 'by Current Writer', $output );
-		$this->assertStringContainsString( 'A note from someone else', $output );
-		$this->assertStringContainsString( 'by Guest Writer', $output );
-		$this->assertStringContainsString( '(no title)', $output );
-		$this->assertStringContainsString( 'word15', $output );
-		$this->assertStringNotContainsString( 'word16', $output );
+		$this->assertIsString( $output );
+
+		$this->assertTrue( $result, 'OTD Widget should return true when posts are rendered.' );
+		$this->assertStringContainsString( 'Published On This Day', $output, 'OTD Widget should render the section heading.' );
+		$this->assertStringContainsString( 'A note from me', $output, 'OTD Widget should render posts by the current user.' );
+		$this->assertStringNotContainsString( 'by Current Writer', $output, 'OTD Widget should not show a byline for the current user.' );
+		$this->assertStringContainsString( 'A note from someone else', $output, 'OTD Widget should render posts by other users.' );
+		$this->assertStringContainsString( 'by Guest Writer', $output, 'OTD Widget should show a byline for other users.' );
+		$this->assertStringContainsString( '(no title)', $output, 'OTD Widget should render a placeholder for untitled posts.' );
+		$this->assertStringContainsString( 'word15', $output, 'OTD Widget should include the first fifteen words of the excerpt for untitled posts.' );
+		$this->assertStringNotContainsString( 'word16', $output, 'OTD Widget should trim the excerpt for untitled posts to fifteen words.' );
 	}
 
 	/**
+	 * Tests that excerpts of unreadable untitled posts are not rendered.
+	 *
 	 * @ticket 65116
 	 *
 	 * @covers ::wp_dashboard_on_this_day
 	 */
-	public function test_section_hides_untitled_excerpt_for_unreadable_posts() {
+	public function test_otd_hides_untitled_excerpt_for_unreadable_posts() {
 		$this->create_matching_post(
 			self::$other_user_id,
 			'',
@@ -205,24 +235,20 @@ public function test_section_hides_untitled_excerpt_for_unreadable_posts() {
 		);
 
 		add_filter( 'wp_dashboard_on_this_day_query_args', array( $this, 'filter_on_this_day_query_private_posts' ) );
-		try {
-			ob_start();
-			wp_dashboard_on_this_day();
-			$output = ob_get_clean();
-		} finally {
-			remove_filter( 'wp_dashboard_on_this_day_query_args', array( $this, 'filter_on_this_day_query_private_posts' ) );
-		}
+		$output = get_echo( 'wp_dashboard_on_this_day' );
 
-		$this->assertStringContainsString( '(no title)', $output );
-		$this->assertStringNotContainsString( 'Unreadable private anniversary memory.', $output );
+		$this->assertStringContainsString( '(no title)', $output, 'OTD Widget should render a placeholder for untitled unreadable posts.' );
+		$this->assertStringNotContainsString( 'Unreadable private anniversary memory.', $output, 'OTD Widget should not render the excerpt of unreadable posts.' );
 	}
 
 	/**
+	 * Tests that excerpts of password-protected untitled posts are not rendered.
+	 *
 	 * @ticket 65116
 	 *
 	 * @covers ::wp_dashboard_on_this_day
 	 */
-	public function test_section_hides_untitled_excerpt_for_password_protected_posts() {
+	public function test_otd_hides_untitled_excerpt_for_password_protected_posts() {
 		$this->create_matching_post(
 			self::$user_id,
 			'',
@@ -233,12 +259,80 @@ public function test_section_hides_untitled_excerpt_for_password_protected_posts
 			)
 		);
 
-		ob_start();
-		wp_dashboard_on_this_day();
-		$output = ob_get_clean();
+		$output = get_echo( 'wp_dashboard_on_this_day' );
 
-		$this->assertStringContainsString( '(no title)', $output );
-		$this->assertStringNotContainsString( 'Password-protected anniversary memory.', $output );
+		$this->assertStringContainsString( '(no title)', $output, 'OTD Widget should render a placeholder for untitled password-protected posts.' );
+		$this->assertStringNotContainsString( 'Password-protected anniversary memory.', $output, 'OTD Widget should not render the excerpt of password-protected posts.' );
+	}
+
+	/**
+	 * Tests that the opt-in form is shown and the list hidden before opting in.
+	 *
+	 * @ticket 65116
+	 *
+	 * @covers ::wp_dashboard_on_this_day
+	 */
+	public function test_otd_activity_is_hidden_before_opt_in() {
+		$this->create_matching_post( self::$user_id, 'A note from me' );
+		$this->assertFalse( get_user_option( 'dashboard_show_on_this_day' ), 'User option should default to false' );
+
+		$otd_activity = get_echo( 'wp_dashboard_on_this_day' );
+		$hidden       = $this->get_hidden_class_by_id( $otd_activity );
+
+		$this->assertArrayHasKey( 'wp-on-this-day-posts', $hidden, 'OTD Widget should render the section container.' );
+		$this->assertFalse( $hidden['wp-on-this-day-posts'], 'OTD Widget section container should not be hidden before the user opts in.' );
+
+		$this->assertArrayHasKey( 'wp-on-this-day-posts-list', $hidden, 'OTD Widget should render the posts list element.' );
+		$this->assertTrue( $hidden['wp-on-this-day-posts-list'], 'OTD Widget posts list should be hidden before the user opts in.' );
+
+		$this->assertArrayHasKey( 'wp-on-this-day-posts-form', $hidden, 'OTD Widget should render the opt-in form element.' );
+		$this->assertFalse( $hidden['wp-on-this-day-posts-form'], 'OTD Widget opt-in form should not be hidden before the user opts in.' );
+	}
+
+	/**
+	 * Tests that the form is not rendered and the list is hidden after opt-out.
+	 *
+	 * @ticket 65116
+	 *
+	 * @covers ::wp_dashboard_on_this_day
+	 */
+	public function test_otd_activity_is_hidden_after_opt_out() {
+		update_user_option( self::$user_id, 'dashboard_show_on_this_day', 'opt-out' );
+		$this->create_matching_post( self::$user_id, 'A note from me' );
+
+		$otd_activity = get_echo( 'wp_dashboard_on_this_day' );
+		$hidden       = $this->get_hidden_class_by_id( $otd_activity );
+
+		$this->assertArrayHasKey( 'wp-on-this-day-posts', $hidden, 'OTD Widget should render the section container.' );
+		$this->assertTrue( $hidden['wp-on-this-day-posts'], 'OTD Widget section container should be hidden after the user opts out.' );
+
+		$this->assertArrayHasKey( 'wp-on-this-day-posts-list', $hidden, 'OTD Widget should render the posts list element.' );
+		$this->assertTrue( $hidden['wp-on-this-day-posts-list'], 'OTD Widget posts list should be hidden after the user opts out.' );
+
+		$this->assertArrayNotHasKey( 'wp-on-this-day-posts-form', $hidden, 'OTD Widget should not render the opt-in form after the user opts out.' );
+	}
+
+	/**
+	 * Tests that the form is not rendered and the list is shown after opt-in.
+	 *
+	 * @ticket 65116
+	 *
+	 * @covers ::wp_dashboard_on_this_day
+	 */
+	public function test_otd_activity_is_displayed_after_opt_in() {
+		update_user_option( self::$user_id, 'dashboard_show_on_this_day', 'opt-in' );
+		$this->create_matching_post( self::$user_id, 'A note from me' );
+
+		$otd_activity = get_echo( 'wp_dashboard_on_this_day' );
+		$hidden       = $this->get_hidden_class_by_id( $otd_activity );
+
+		$this->assertArrayHasKey( 'wp-on-this-day-posts', $hidden, 'OTD Widget should render the section container.' );
+		$this->assertFalse( $hidden['wp-on-this-day-posts'], 'OTD Widget section container should not be hidden after the user opts in.' );
+
+		$this->assertArrayHasKey( 'wp-on-this-day-posts-list', $hidden, 'OTD Widget should render the posts list element.' );
+		$this->assertFalse( $hidden['wp-on-this-day-posts-list'], 'OTD Widget posts list should not be hidden after the user opts in.' );
+
+		$this->assertArrayNotHasKey( 'wp-on-this-day-posts-form', $hidden, 'OTD Widget should not render the opt-in form after the user opts in.' );
 	}
 
 	/**
@@ -247,15 +341,15 @@ public function test_section_hides_untitled_excerpt_for_password_protected_posts
 	 * @covers ::wp_dashboard_site_activity
 	 */
 	public function test_activity_renders_no_activity_message_without_posts() {
-		ob_start();
-		wp_dashboard_site_activity();
-		$output = ob_get_clean();
+		$output = get_echo( 'wp_dashboard_site_activity' );
 
-		$this->assertStringContainsString( 'No activity yet!', $output );
-		$this->assertStringNotContainsString( 'Published On This Day', $output );
+		$this->assertStringContainsString( 'No activity yet!', $output, 'Activity Widget should render the empty state when there are no posts.' );
+		$this->assertStringNotContainsString( 'Published On This Day', $output, 'Activity Widget should not render the OTD section when there are no posts.' );
 	}
 
 	/**
+	 * Tests that On This Day posts are not repeated in Recently Published.
+	 *
 	 * @ticket 65116
 	 *
 	 * @covers ::wp_dashboard_site_activity
@@ -271,13 +365,11 @@ public function test_activity_does_not_repeat_on_this_day_posts_in_recently_publ
 			)
 		);
 
-		ob_start();
-		wp_dashboard_site_activity();
-		$output = ob_get_clean();
+		$output = get_echo( 'wp_dashboard_site_activity' );
 
-		$this->assertStringContainsString( 'Published On This Day', $output );
-		$this->assertSame( 1, preg_match( '/<div id="published-posts".*?<\/div>/s', $output, $recent_posts ) );
-		$this->assertStringNotContainsString( 'One anniversary mention', $recent_posts[0] );
+		$this->assertStringContainsString( 'Published On This Day', $output, 'Activity Widget should render the OTD section.' );
+		$this->assertSame( 1, preg_match( '/<div id="published-posts".*?<\/div>/s', $output, $recent_posts ), 'Activity Widget should render the recently published section.' );
+		$this->assertStringNotContainsString( 'One anniversary mention', $recent_posts[0], 'Recently published section should not repeat posts shown in the OTD section.' );
 	}
 
 	/**
@@ -301,23 +393,15 @@ public function test_recent_comments_are_rendered_only_in_their_dedicated_widget
 			)
 		);
 
-		ob_start();
-		wp_dashboard_site_activity();
-		$activity_output = ob_get_clean();
+		$activity_output = get_echo( 'wp_dashboard_site_activity' );
+		$comments_output = get_echo( 'wp_dashboard_recent_comments_widget' );
+		$direct_output   = get_echo( 'wp_dashboard_recent_comments' );
 
-		ob_start();
-		wp_dashboard_recent_comments_widget();
-		$comments_output = ob_get_clean();
-
-		ob_start();
-		wp_dashboard_recent_comments();
-		$direct_output = ob_get_clean();
-
-		$this->assertStringNotContainsString( 'A comment in its own widget.', $activity_output );
-		$this->assertStringContainsString( 'No activity yet!', $activity_output );
-		$this->assertStringContainsString( 'A comment in its own widget.', $comments_output );
-		$this->assertStringNotContainsString( '<h3>Recent Comments</h3>', $comments_output );
-		$this->assertStringContainsString( '<h3>Recent Comments</h3>', $direct_output );
+		$this->assertStringNotContainsString( 'A comment in its own widget.', $activity_output, 'Activity Widget should not render recent comments.' );
+		$this->assertStringContainsString( 'No activity yet!', $activity_output, 'Activity Widget should render the empty state when comments are the only activity.' );
+		$this->assertStringContainsString( 'A comment in its own widget.', $comments_output, 'Recent Comments Widget should render recent comments.' );
+		$this->assertStringNotContainsString( '<h3>Recent Comments</h3>', $comments_output, 'Recent Comments Widget should not render the section heading.' );
+		$this->assertStringContainsString( '<h3>Recent Comments</h3>', $direct_output, 'Recent comments rendered directly should include the section heading.' );
 	}
 
 	/**
@@ -335,9 +419,7 @@ public function test_recent_comments_widget_renders_empty_state_when_user_has_no
 		);
 		wp_set_current_user( self::factory()->user->create( array( 'role' => 'subscriber' ) ) );
 
-		ob_start();
-		wp_dashboard_recent_comments_widget();
-		$output = ob_get_clean();
+		$output = get_echo( 'wp_dashboard_recent_comments_widget' );
 
 		$this->assertStringContainsString( 'No comments to show.', $output );
 	}
@@ -347,56 +429,69 @@ public function test_recent_comments_widget_renders_empty_state_when_user_has_no
 	 *
 	 * @covers ::_wp_dashboard_has_received_comments
 	 * @covers ::wp_dashboard_setup
+	 *
+	 * @global array{ dashboard: array{ normal: array{ core: array<string, mixed> }, ... }, ... } $wp_meta_boxes
 	 */
 	public function test_recent_comments_widget_remains_registered_after_comments_are_deleted() {
+		global $wp_meta_boxes;
 		add_filter( 'pre_http_request', array( $this, 'mock_http_request_failure' ) );
 
-		try {
-			wp_dashboard_setup();
-			$this->assertArrayNotHasKey( 'dashboard_recent_comments', $GLOBALS['wp_meta_boxes']['dashboard']['normal']['core'] );
+		wp_dashboard_setup();
+		$this->assertArrayHasKey( 'dashboard', $wp_meta_boxes );
+		$this->assertArrayNotHasKey( 'dashboard_recent_comments', $wp_meta_boxes['dashboard']['normal']['core'], 'Recent Comments Widget should not be registered before any comments are received.' );
 
-			unset( $GLOBALS['wp_meta_boxes']['dashboard'] );
+		unset( $wp_meta_boxes['dashboard'] );
 
-			$post_id    = self::factory()->post->create();
-			$comment_id = self::factory()->comment->create( array( 'comment_post_ID' => $post_id ) );
+		$post_id    = self::factory()->post->create();
+		$comment_id = self::factory()->comment->create( array( 'comment_post_ID' => $post_id ) );
 
-			wp_dashboard_setup();
-			$this->assertArrayHasKey( 'dashboard_recent_comments', $GLOBALS['wp_meta_boxes']['dashboard']['normal']['core'] );
-			$this->assertSame(
-				'wp_dashboard_recent_comments_widget',
-				$GLOBALS['wp_meta_boxes']['dashboard']['normal']['core']['dashboard_recent_comments']['callback']
-			);
-			$this->assertSame( 1, get_option( 'dashboard_recent_comments_widget_registered' ) );
+		wp_dashboard_setup();
+		$this->assertArrayHasKey( 'dashboard', $wp_meta_boxes );
+		$this->assertArrayHasKey( 'dashboard_recent_comments', $wp_meta_boxes['dashboard']['normal']['core'], 'Recent Comments Widget should be registered once a comment is received.' );
+		$this->assertSame(
+			'wp_dashboard_recent_comments_widget',
+			$wp_meta_boxes['dashboard']['normal']['core']['dashboard_recent_comments']['callback'],
+			'Recent Comments Widget should use the dedicated widget callback.'
+		);
+		$this->assertSame( 1, get_option( 'dashboard_recent_comments_widget_registered' ), 'Recent Comments Widget registration should be stored in an option.' );
 
-			wp_delete_comment( $comment_id, true );
-			unset( $GLOBALS['wp_meta_boxes']['dashboard'] );
+		wp_delete_comment( $comment_id, true );
+		unset( $wp_meta_boxes['dashboard'] );
 
-			wp_dashboard_setup();
-			$this->assertArrayHasKey( 'dashboard_recent_comments', $GLOBALS['wp_meta_boxes']['dashboard']['normal']['core'] );
-		} finally {
-			remove_filter( 'pre_http_request', array( $this, 'mock_http_request_failure' ) );
-		}
+		wp_dashboard_setup();
+		$this->assertArrayHasKey( 'dashboard_recent_comments', $wp_meta_boxes['dashboard']['normal']['core'], 'Recent Comments Widget should remain registered after all comments are deleted.' );
 	}
 
 	/**
-	 * Mocks an HTTP request failure during dashboard setup.
+	 * Gets whether each element with an ID has the `hidden` class.
 	 *
-	 * @return WP_Error Mock request error.
+	 * @param string $html HTML fragment to parse.
+	 * @return array<string, bool> Whether the element has the `hidden` class, keyed by element ID.
 	 */
-	public function mock_http_request_failure() {
-		return new WP_Error( 'http_request_failed' );
+	private function get_hidden_class_by_id( string $html ): array {
+		$processor = WP_HTML_Processor::create_fragment( $html );
+		$this->assertInstanceOf( WP_HTML_Processor::class, $processor );
+		$hidden = array();
+
+		while ( $processor->next_tag() ) {
+			$id = $processor->get_attribute( 'id' );
+			if ( ! is_string( $id ) ) {
+				continue;
+			}
+
+			$hidden[ $id ] = true === $processor->has_class( 'hidden' );
+		}
+
+		return $hidden;
 	}
 
 	/**
-	 * Sets the On This Day query limit to three.
+	 * Mocks an HTTP request failure during dashboard setup.
 	 *
-	 * @param array $args Query arguments.
-	 * @return array Filtered query arguments.
+	 * @return WP_Error Mock request error.
 	 */
-	public function filter_on_this_day_query_limit( $args ) {
-		$args['posts_per_page'] = 3;
-
-		return $args;
+	public function mock_http_request_failure() {
+		return new WP_Error( 'http_request_failed' );
 	}
 
 	/**