diff --git a/src/wp-includes/html-api/class-wp-html-processor.php b/src/wp-includes/html-api/class-wp-html-processor.php
index 975f21a0f0d77..f8653022454b6 100644
--- a/src/wp-includes/html-api/class-wp-html-processor.php
+++ b/src/wp-includes/html-api/class-wp-html-processor.php
@@ -609,25 +609,30 @@ public function next_token(): bool {
 		 *       until there are events or until there are no more
 		 *       tokens works in the meantime and isn't obviously wrong.
 		 */
-		while ( empty( $this->element_queue ) && $this->step() ) {
-			continue;
+		if ( empty( $this->element_queue ) && $this->step() ) {
+			return $this->next_token();
 		}
 
 		// Process the next event on the queue.
 		$this->current_element = array_shift( $this->element_queue );
 		if ( ! isset( $this->current_element ) ) {
-			return false;
+			// There are no tokens left, so close all remaining open elements.
+			while ( $this->state->stack_of_open_elements->pop() ) {
+				continue;
+			}
+
+			return empty( $this->element_queue ) ? false : $this->next_token();
 		}
 
 		$is_pop = WP_HTML_Stack_Event::POP === $this->current_element->operation;
 
 		/*
 		 * The root node only exists in the fragment parser, and closing it
-		 * indicates that the parse is complete. Stop before popping if from
+		 * indicates that the parse is complete. Stop before popping it from
 		 * the breadcrumbs.
 		 */
 		if ( 'root-node' === $this->current_element->token->bookmark_name ) {
-			return ! $is_pop && $this->next_token();
+			return $this->next_token();
 		}
 
 		// Adjust the breadcrumbs for this event.
@@ -638,7 +643,7 @@ public function next_token(): bool {
 		}
 
 		// Avoid sending close events for elements which don't expect a closing.
-		if ( $is_pop && ! static::expects_closer( $this->current_element->token ) ) {
+		if ( $is_pop && ! $this->expects_closer( $this->current_element->token ) ) {
 			return $this->next_token();
 		}
 
diff --git a/tests/phpunit/tests/html-api/wpHtmlProcessor.php b/tests/phpunit/tests/html-api/wpHtmlProcessor.php
index 12f36ca742989..01e0f4f02c0b5 100644
--- a/tests/phpunit/tests/html-api/wpHtmlProcessor.php
+++ b/tests/phpunit/tests/html-api/wpHtmlProcessor.php
@@ -475,6 +475,47 @@ public static function data_html_with_target_element_and_depth_of_next_node_in_b
 		);
 	}
 
+	/**
+	 * Ensures that elements which are unopened at the end of a document are implicitly closed.
+	 *
+	 * @ticket 61576
+	 */
+	public function test_closes_unclosed_elements() {
+		$processor = WP_HTML_Processor::create_fragment( '<div><p><span>' );
+
+		$this->assertTrue(
+			$processor->next_tag( 'SPAN' ),
+			'Could not find SPAN element: check test setup.'
+		);
+
+		// This is the end of the document, but there should be three closing events.
+		$processor->next_token();
+		$this->assertSame(
+			'SPAN',
+			$processor->get_tag(),
+			'Should have found implicit SPAN closing tag.'
+		);
+
+		$processor->next_token();
+		$this->assertSame(
+			'P',
+			$processor->get_tag(),
+			'Should have found implicit P closing tag.'
+		);
+
+		$processor->next_token();
+		$this->assertSame(
+			'DIV',
+			$processor->get_tag(),
+			'Should have found implicit DIV closing tag.'
+		);
+
+		$this->assertFalse(
+			$processor->next_token(),
+			"Should have failed to find any more tokens but found a '{$processor->get_token_name()}'"
+		);
+	}
+
 	/**
 	 * Ensures that subclasses can be created from ::create_fragment method.
 	 *