From 8ae650bf728cf0afad7e1964b6bb95dcfc7f9dde Mon Sep 17 00:00:00 2001
From: thelovekesh <lovekesh.kumar@rtcamp.com>
Date: Sun, 25 Aug 2024 13:01:44 +0530
Subject: [PATCH 01/13] Update wwo script loading strategy

---
 plugins/web-worker-offloading/hooks.php | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/plugins/web-worker-offloading/hooks.php b/plugins/web-worker-offloading/hooks.php
index 77989c00b4..877fda376f 100644
--- a/plugins/web-worker-offloading/hooks.php
+++ b/plugins/web-worker-offloading/hooks.php
@@ -80,13 +80,10 @@ function wwo_init(): void {
  * @return string[] Array of script handles.
  */
 function wwo_update_script_strategy( $script_handles ): array {
-	$script_handles = array_intersect( (array) $script_handles, array_keys( wp_scripts()->registered ) );
 	foreach ( $script_handles as $handle ) {
-		if ( in_array( 'web-worker-offloading', wp_scripts()->registered[ $handle ]->deps, true ) ) {
-			if ( false === wp_scripts()->get_data( $handle, 'strategy' ) ) {
-				wp_script_add_data( $handle, 'strategy', 'async' ); // The 'defer' strategy would work as well.
-				wp_script_add_data( $handle, 'wwo_strategy_added', true );
-			}
+		if ( (bool) wp_scripts()->get_data( $handle, 'worker' ) && false === wp_scripts()->get_data( $handle, 'strategy' ) ) {
+			wp_script_add_data( $handle, 'strategy', 'async' ); // The 'defer' strategy would work as well.
+			wp_script_add_data( $handle, 'wwo_strategy_added', true );
 		}
 	}
 
@@ -106,8 +103,7 @@ function wwo_update_script_strategy( $script_handles ): array {
 function wwo_update_script_type( $tag, string $handle ) {
 	if (
 		is_string( $tag ) &&
-		array_key_exists( $handle, wp_scripts()->registered ) &&
-		in_array( 'web-worker-offloading', wp_scripts()->registered[ $handle ]->deps, true )
+		(bool) wp_scripts()->get_data( $handle, 'worker' )
 	) {
 		$html_processor = new WP_HTML_Tag_Processor( $tag );
 

From 1a0d378d0cac49997686dcc3882e32e2a5212922 Mon Sep 17 00:00:00 2001
From: thelovekesh <lovekesh.kumar@rtcamp.com>
Date: Sun, 25 Aug 2024 14:17:12 +0530
Subject: [PATCH 02/13] Add function to add web-worker-offloading script as dep
 if worker is added to script data

---
 plugins/web-worker-offloading/hooks.php | 28 +++++++++++++------------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/plugins/web-worker-offloading/hooks.php b/plugins/web-worker-offloading/hooks.php
index 877fda376f..ee58d58035 100644
--- a/plugins/web-worker-offloading/hooks.php
+++ b/plugins/web-worker-offloading/hooks.php
@@ -68,28 +68,30 @@ function wwo_init(): void {
 add_action( 'wp_enqueue_scripts', 'wwo_init' );
 
 /**
- * Marks scripts with `web-worker-offloading` dependency as async.
+ * Adds `web-worker-offloading` as dependency to scripts with `worker` data. Also, marks their strategy as `async`.
  *
  * This is needed because scripts offloaded to a worker thread can be considered async. However, they may include `before` and `after` inline
  * scripts that need sequential execution. Once marked as async, `filter_eligible_strategies()` determines if the
  * script is eligible for async execution. If so, it will be offloaded to the worker thread.
  *
- * @since 0.1.0
- *
- * @param string[]|mixed $script_handles Array of script handles.
- * @return string[] Array of script handles.
+ * @since n.e.x.t
  */
-function wwo_update_script_strategy( $script_handles ): array {
-	foreach ( $script_handles as $handle ) {
-		if ( (bool) wp_scripts()->get_data( $handle, 'worker' ) && false === wp_scripts()->get_data( $handle, 'strategy' ) ) {
-			wp_script_add_data( $handle, 'strategy', 'async' ); // The 'defer' strategy would work as well.
-			wp_script_add_data( $handle, 'wwo_strategy_added', true );
+function wwo_add_dependency_to_worker_scripts(): void {
+	foreach ( wp_scripts()->registered as $dep ) {
+		if (
+			(bool) wp_scripts()->get_data( $dep->handle, 'worker') &&
+			! in_array( 'web-worker-offloading', wp_scripts()->registered[ $dep->handle ]->deps, true )
+		) {
+			wp_scripts()->registered[ $dep->handle ]->deps[] = 'web-worker-offloading';
+
+			if ( false === wp_scripts()->get_data( $dep->handle, 'strategy' ) ) {
+				wp_script_add_data( $dep->handle, 'strategy', 'async' ); // The 'defer' strategy would work as well.
+				wp_script_add_data( $dep->handle, 'wwo_strategy_added', true );
+			}
 		}
 	}
-
-	return $script_handles;
 }
-add_filter( 'print_scripts_array', 'wwo_update_script_strategy' );
+add_action( 'wp_print_scripts', 'wwo_add_dependency_to_worker_scripts' );
 
 /**
  * Updates script type for handles having `web-worker-offloading` as dependency.

From 32c938f9e3e517da9886203070d9049bc96ab61d Mon Sep 17 00:00:00 2001
From: thelovekesh <lovekesh.kumar@rtcamp.com>
Date: Sun, 25 Aug 2024 14:17:40 +0530
Subject: [PATCH 03/13] Update test cases for updating wwo script type

---
 .../tests/test-web-worker-offloading.php      | 24 ++++++++++++-------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
index f587a5495a..c196f74733 100644
--- a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
+++ b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
@@ -107,64 +107,72 @@ public static function data_update_script_types(): array {
 			),
 			'add-script-for-web-worker-offloading'       => array(
 				'set_up'         => static function (): void {
-					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array( 'web-worker-offloading' ), '1.0.0', true );
+					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', true );
+					wp_script_add_data( 'foo', 'worker', true );
 				},
 				'expected'       => '{{ wwo_config }}{{ wwo_inline_script }}<script type="text/partytown" src="https://example.com/foo.js?ver=1.0.0" id="foo-js"  ></script>',
 				'doing_it_wrong' => false,
 			),
 			'add-defer-script-for-web-worker-offloading' => array(
 				'set_up'         => static function (): void {
-					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array( 'web-worker-offloading' ), '1.0.0', array( 'strategy' => 'defer' ) );
+					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', array( 'strategy' => 'defer' ) );
+					wp_script_add_data( 'foo', 'worker', true );
 				},
 				'expected'       => '{{ wwo_config }}{{ wwo_inline_script }}<script type="text/partytown" src="https://example.com/foo.js?ver=1.0.0" id="foo-js" defer data-wp-strategy="defer"></script>',
 				'doing_it_wrong' => false,
 			),
 			'add-async-script-for-web-worker-offloading' => array(
 				'set_up'         => static function (): void {
-					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array( 'web-worker-offloading' ), '1.0.0', array( 'strategy' => 'async' ) );
+					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', array( 'strategy' => 'async' ) );
+					wp_script_add_data( 'foo', 'worker', true );
 				},
 				'expected'       => '{{ wwo_config }}{{ wwo_inline_script }}<script type="text/partytown" src="https://example.com/foo.js?ver=1.0.0" id="foo-js" async data-wp-strategy="async"></script>',
 				'doing_it_wrong' => false,
 			),
 			'add-script-for-web-worker-offloading-with-before-data' => array(
 				'set_up'         => static function (): void {
-					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array( 'web-worker-offloading' ), '1.0.0', true );
+					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', true );
 					wp_add_inline_script( 'foo', 'console.log("Hello, World!");', 'before' );
+					wp_script_add_data( 'foo', 'worker', true );
 				},
 				'expected'       => '{{ wwo_config }}{{ wwo_inline_script }}<script id="foo-js-before">console.log("Hello, World!");</script><script type="text/partytown" src="https://example.com/foo.js?ver=1.0.0" id="foo-js"  ></script>',
 				'doing_it_wrong' => false,
 			),
 			'add-script-for-web-worker-offloading-with-after-data' => array(
 				'set_up'         => static function (): void {
-					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array( 'web-worker-offloading' ), '1.0.0', true );
+					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', true );
 					wp_add_inline_script( 'foo', 'console.log("Hello, World!");', 'after' );
+					wp_script_add_data( 'foo', 'worker', true );
 				},
 				'expected'       => '{{ wwo_config }}{{ wwo_inline_script }}<script src="https://example.com/foo.js?ver=1.0.0" id="foo-js" ></script><script id="foo-js-after">console.log("Hello, World!");</script>',
 				'doing_it_wrong' => true,
 			),
 			'add-script-for-web-worker-offloading-with-before-and-after-data' => array(
 				'set_up'         => static function (): void {
-					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array( 'web-worker-offloading' ), '1.0.0', true );
+					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', true );
 					wp_add_inline_script( 'foo', 'console.log("Hello, World!");', 'before' );
 					wp_add_inline_script( 'foo', 'console.log("Hello, World!");', 'after' );
+					wp_script_add_data( 'foo', 'worker', true );
 				},
 				'expected'       => '{{ wwo_config }}{{ wwo_inline_script }}<script id="foo-js-before">console.log("Hello, World!");</script><script src="https://example.com/foo.js?ver=1.0.0" id="foo-js" ></script><script id="foo-js-after">console.log("Hello, World!");</script>',
 				'doing_it_wrong' => true,
 			),
 			'add-async-script-for-web-worker-offloading-with-before-and-after-data' => array(
 				'set_up'         => static function (): void {
-					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array( 'web-worker-offloading' ), '1.0.0', array( 'strategy' => 'async' ) );
+					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', array( 'strategy' => 'async' ) );
 					wp_add_inline_script( 'foo', 'console.log("Hello, World!");', 'before' );
 					wp_add_inline_script( 'foo', 'console.log("Hello, World!");', 'after' );
+					wp_script_add_data( 'foo', 'worker', true );
 				},
 				'expected'       => '{{ wwo_config }}{{ wwo_inline_script }}<script id="foo-js-before">console.log("Hello, World!");</script><script src="https://example.com/foo.js?ver=1.0.0" id="foo-js" data-wp-strategy="async"></script><script id="foo-js-after">console.log("Hello, World!");</script>',
 				'doing_it_wrong' => true,
 			),
 			'add-defer-script-for-web-worker-offloading-with-before-and-after-data' => array(
 				'set_up'         => static function (): void {
-					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array( 'web-worker-offloading' ), '1.0.0', array( 'strategy' => 'defer' ) );
+					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', array( 'strategy' => 'defer' ) );
 					wp_add_inline_script( 'foo', 'console.log("Hello, World!");', 'before' );
 					wp_add_inline_script( 'foo', 'console.log("Hello, World!");', 'after' );
+					wp_script_add_data( 'foo', 'worker', true );
 				},
 				'expected'       => '{{ wwo_config }}{{ wwo_inline_script }}<script id="foo-js-before">console.log("Hello, World!");</script><script src="https://example.com/foo.js?ver=1.0.0" id="foo-js" data-wp-strategy="defer"></script><script id="foo-js-after">console.log("Hello, World!");</script>',
 				'doing_it_wrong' => true,

From 1ff2525310990c6340dad6de52cdca74a2aeeeeb Mon Sep 17 00:00:00 2001
From: thelovekesh <lovekesh.kumar@rtcamp.com>
Date: Sun, 25 Aug 2024 14:21:33 +0530
Subject: [PATCH 04/13] Update function name for updating worker data scripts
 deps

---
 plugins/web-worker-offloading/hooks.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/plugins/web-worker-offloading/hooks.php b/plugins/web-worker-offloading/hooks.php
index ee58d58035..6da5ee0f27 100644
--- a/plugins/web-worker-offloading/hooks.php
+++ b/plugins/web-worker-offloading/hooks.php
@@ -76,7 +76,7 @@ function wwo_init(): void {
  *
  * @since n.e.x.t
  */
-function wwo_add_dependency_to_worker_scripts(): void {
+function wwo_update_worker_scripts_deps_and_strategy(): void {
 	foreach ( wp_scripts()->registered as $dep ) {
 		if (
 			(bool) wp_scripts()->get_data( $dep->handle, 'worker') &&
@@ -91,7 +91,7 @@ function wwo_add_dependency_to_worker_scripts(): void {
 		}
 	}
 }
-add_action( 'wp_print_scripts', 'wwo_add_dependency_to_worker_scripts' );
+add_action( 'wp_print_scripts', 'wwo_update_worker_scripts_deps_and_strategy' );
 
 /**
  * Updates script type for handles having `web-worker-offloading` as dependency.

From a9cf46c2b8d2309429b6731f25549b4db215ac07 Mon Sep 17 00:00:00 2001
From: thelovekesh <lovekesh.kumar@rtcamp.com>
Date: Sun, 25 Aug 2024 14:23:11 +0530
Subject: [PATCH 05/13] Update covers tag

---
 .../web-worker-offloading/tests/test-web-worker-offloading.php  | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
index c196f74733..b634354d80 100644
--- a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
+++ b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
@@ -184,7 +184,7 @@ public static function data_update_script_types(): array {
 	 * Test `wwo_update_script_type`.
 	 *
 	 * @covers ::wwo_update_script_type
-	 * @covers ::wwo_update_script_strategy
+	 * @covers ::wwo_update_worker_scripts_deps_and_strategy
 	 *
 	 * @dataProvider data_update_script_types
 	 *

From a75c06278a4165052a7e8fc5e4e3f3c5479c23c0 Mon Sep 17 00:00:00 2001
From: thelovekesh <lovekesh.kumar@rtcamp.com>
Date: Sun, 25 Aug 2024 14:32:26 +0530
Subject: [PATCH 06/13] Fix spacing

---
 plugins/web-worker-offloading/hooks.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/plugins/web-worker-offloading/hooks.php b/plugins/web-worker-offloading/hooks.php
index 6da5ee0f27..f9ca9bf68d 100644
--- a/plugins/web-worker-offloading/hooks.php
+++ b/plugins/web-worker-offloading/hooks.php
@@ -79,7 +79,7 @@ function wwo_init(): void {
 function wwo_update_worker_scripts_deps_and_strategy(): void {
 	foreach ( wp_scripts()->registered as $dep ) {
 		if (
-			(bool) wp_scripts()->get_data( $dep->handle, 'worker') &&
+			(bool) wp_scripts()->get_data( $dep->handle, 'worker' ) &&
 			! in_array( 'web-worker-offloading', wp_scripts()->registered[ $dep->handle ]->deps, true )
 		) {
 			wp_scripts()->registered[ $dep->handle ]->deps[] = 'web-worker-offloading';

From 6c255e72e0a55a057610d55cdb390d31e373f645 Mon Sep 17 00:00:00 2001
From: Weston Ruter <westonruter@google.com>
Date: Thu, 26 Sep 2024 14:25:23 -0700
Subject: [PATCH 07/13] Use wp_default_scripts instead of wp_enqueue_scripts
 for script registration

---
 plugins/web-worker-offloading/hooks.php            | 14 ++++++++------
 .../tests/test-web-worker-offloading.php           | 11 ++++-------
 2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/plugins/web-worker-offloading/hooks.php b/plugins/web-worker-offloading/hooks.php
index f9ca9bf68d..2f98c060ef 100644
--- a/plugins/web-worker-offloading/hooks.php
+++ b/plugins/web-worker-offloading/hooks.php
@@ -36,17 +36,19 @@ function wwo_get_configuration(): array {
 }
 
 /**
- * Initializes Web Worker Offloading.
+ * Registers defaults scripts for Web Worker Offloading.
  *
  * @since 0.1.0
+ *
+ * @param WP_Scripts $scripts WP_Scripts instance.
  */
-function wwo_init(): void {
+function wwo_register_default_scripts( WP_Scripts $scripts ): void {
 	$partytown_js = file_get_contents( __DIR__ . '/build/partytown.js' ); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents -- It's a local filesystem path not a remote request.
 	if ( false === $partytown_js ) {
 		return;
 	}
 
-	wp_register_script(
+	$scripts->add(
 		'web-worker-offloading',
 		'',
 		array(),
@@ -54,7 +56,7 @@ function wwo_init(): void {
 		array( 'in_footer' => false )
 	);
 
-	wp_add_inline_script(
+	$scripts->add_inline_script(
 		'web-worker-offloading',
 		sprintf(
 			'window.partytown = %s;',
@@ -63,9 +65,9 @@ function wwo_init(): void {
 		'before'
 	);
 
-	wp_add_inline_script( 'web-worker-offloading', $partytown_js );
+	$scripts->add_inline_script( 'web-worker-offloading', $partytown_js );
 }
-add_action( 'wp_enqueue_scripts', 'wwo_init' );
+add_action( 'wp_default_scripts', 'wwo_register_default_scripts' );
 
 /**
  * Adds `web-worker-offloading` as dependency to scripts with `worker` data. Also, marks their strategy as `async`.
diff --git a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
index b634354d80..40e0cff2d2 100644
--- a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
+++ b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
@@ -60,13 +60,13 @@ static function ( $config ) {
 	}
 
 	/**
-	 * @covers ::wwo_init
+	 * @covers ::wwo_register_default_scripts
 	 */
-	public function test_wwo_init(): void {
-		$this->assertEquals( 10, has_action( 'wp_enqueue_scripts', 'wwo_init' ) );
+	public function test_wwo_register_default_scripts(): void {
+		$this->assertEquals( 10, has_action( 'wp_default_scripts', 'wwo_register_default_scripts' ) );
 
 		// Register scripts.
-		wwo_init();
+		wp_scripts();
 
 		$wp_content_dir   = WP_CONTENT_DIR;
 		$partytown_config = wwo_get_configuration();
@@ -193,9 +193,6 @@ public static function data_update_script_types(): array {
 	 * @param bool    $doing_it_wrong Whether to expect a `_doing_it_wrong` notice.
 	 */
 	public function test_update_script_types( Closure $set_up, string $expected, bool $doing_it_wrong ): void {
-		// Setup.
-		wwo_init();
-
 		$wwo_config_data        = wp_scripts()->get_inline_script_data( 'web-worker-offloading', 'before' );
 		$wwo_inline_script_data = wp_scripts()->get_inline_script_data( 'web-worker-offloading', 'after' );
 

From 34405c2cd1fb1f545af9c0f16580fcd817032908 Mon Sep 17 00:00:00 2001
From: Weston Ruter <westonruter@google.com>
Date: Thu, 26 Sep 2024 14:29:27 -0700
Subject: [PATCH 08/13] Remove unrelated assertions from testing
 wwo_register_default_scripts

---
 .../tests/test-web-worker-offloading.php                    | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
index 40e0cff2d2..f97c8f3d60 100644
--- a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
+++ b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
@@ -83,12 +83,6 @@ public function test_wwo_register_default_scripts(): void {
 		);
 		$this->assertEquals( file_get_contents( $partytown_lib . 'partytown.js' ), $after_data );
 		$this->assertTrue( wp_script_is( 'web-worker-offloading', 'registered' ) );
-
-		// Ensure that Partytown is enqueued when a script depends on it.
-		wp_enqueue_script( 'partytown-test', 'https://example.com/test.js', array( 'web-worker-offloading' ) );
-
-		$this->assertTrue( wp_script_is( 'web-worker-offloading', 'enqueued' ) );
-		$this->assertTrue( wp_script_is( 'partytown-test', 'enqueued' ) );
 	}
 
 	/**

From 0c2d7b23b70b4ede5abc30ff54e922e3594ba97d Mon Sep 17 00:00:00 2001
From: Weston Ruter <westonruter@google.com>
Date: Thu, 26 Sep 2024 15:09:00 -0700
Subject: [PATCH 09/13] Use print_scripts_array filter instead of
 wp_print_scripts action

---
 plugins/web-worker-offloading/hooks.php       | 37 ++++++-----
 .../tests/test-web-worker-offloading.php      | 63 ++++++++++++++-----
 2 files changed, 70 insertions(+), 30 deletions(-)

diff --git a/plugins/web-worker-offloading/hooks.php b/plugins/web-worker-offloading/hooks.php
index 2f98c060ef..b41cbf837b 100644
--- a/plugins/web-worker-offloading/hooks.php
+++ b/plugins/web-worker-offloading/hooks.php
@@ -70,30 +70,35 @@ function wwo_register_default_scripts( WP_Scripts $scripts ): void {
 add_action( 'wp_default_scripts', 'wwo_register_default_scripts' );
 
 /**
- * Adds `web-worker-offloading` as dependency to scripts with `worker` data. Also, marks their strategy as `async`.
+ * Prepends web-worker-offloading to the list of scripts to print if one of the queued scripts is offloaded to a worker.
  *
- * This is needed because scripts offloaded to a worker thread can be considered async. However, they may include `before` and `after` inline
- * scripts that need sequential execution. Once marked as async, `filter_eligible_strategies()` determines if the
- * script is eligible for async execution. If so, it will be offloaded to the worker thread.
+ * This also marks their strategy as `async`. This is needed because scripts offloaded to a worker thread can be
+ * considered async. However, they may include `before` and `after` inline scripts that need sequential execution. Once
+ * marked as async, `filter_eligible_strategies()` determines if the script is eligible for async execution. If so, it
+ * will be offloaded to the worker thread.
  *
- * @since n.e.x.t
+ * @since 0.1.0
+ *
+ * @param string[]|mixed $to_do An array of enqueued script dependency handles.
+ * @return string[] Script handles.
  */
-function wwo_update_worker_scripts_deps_and_strategy(): void {
-	foreach ( wp_scripts()->registered as $dep ) {
-		if (
-			(bool) wp_scripts()->get_data( $dep->handle, 'worker' ) &&
-			! in_array( 'web-worker-offloading', wp_scripts()->registered[ $dep->handle ]->deps, true )
-		) {
-			wp_scripts()->registered[ $dep->handle ]->deps[] = 'web-worker-offloading';
+function wwo_filter_print_scripts_array( $to_do ): array {
+	$scripts = wp_scripts();
+	foreach ( (array) $to_do as $handle ) {
+		if ( true === $scripts->get_data( $handle, 'worker' ) ) {
+			$scripts->set_group( 'web-worker-offloading', false, 0 ); // Try to print in the head.
+			array_unshift( $to_do, 'web-worker-offloading' );
 
-			if ( false === wp_scripts()->get_data( $dep->handle, 'strategy' ) ) {
-				wp_script_add_data( $dep->handle, 'strategy', 'async' ); // The 'defer' strategy would work as well.
-				wp_script_add_data( $dep->handle, 'wwo_strategy_added', true );
+			// TODO: This should be reconsidered because scripts needing to be offloaded will often have after scripts. See <https://github.com/WordPress/performance/pull/1497/files#r1733538721>.
+			if ( false === wp_scripts()->get_data( $handle, 'strategy' ) ) {
+				wp_script_add_data( $handle, 'strategy', 'async' ); // The 'defer' strategy would work as well.
+				wp_script_add_data( $handle, 'wwo_strategy_added', true );
 			}
 		}
 	}
+	return $to_do;
 }
-add_action( 'wp_print_scripts', 'wwo_update_worker_scripts_deps_and_strategy' );
+add_filter( 'print_scripts_array', 'wwo_filter_print_scripts_array' );
 
 /**
  * Updates script type for handles having `web-worker-offloading` as dependency.
diff --git a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
index f97c8f3d60..b2e614151d 100644
--- a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
+++ b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
@@ -178,7 +178,7 @@ public static function data_update_script_types(): array {
 	 * Test `wwo_update_script_type`.
 	 *
 	 * @covers ::wwo_update_script_type
-	 * @covers ::wwo_update_worker_scripts_deps_and_strategy
+	 * @covers ::wwo_filter_print_scripts_array
 	 *
 	 * @dataProvider data_update_script_types
 	 *
@@ -187,19 +187,7 @@ public static function data_update_script_types(): array {
 	 * @param bool    $doing_it_wrong Whether to expect a `_doing_it_wrong` notice.
 	 */
 	public function test_update_script_types( Closure $set_up, string $expected, bool $doing_it_wrong ): void {
-		$wwo_config_data        = wp_scripts()->get_inline_script_data( 'web-worker-offloading', 'before' );
-		$wwo_inline_script_data = wp_scripts()->get_inline_script_data( 'web-worker-offloading', 'after' );
-
-		$expected = str_replace(
-			'{{ wwo_config }}',
-			wp_get_inline_script_tag( $wwo_config_data, array( 'id' => 'web-worker-offloading-js-before' ) ),
-			$expected
-		);
-		$expected = str_replace(
-			'{{ wwo_inline_script }}',
-			wp_get_inline_script_tag( $wwo_inline_script_data, array( 'id' => 'web-worker-offloading-js-after' ) ),
-			$expected
-		);
+		$expected = $this->replace_placeholders( $expected );
 
 		if ( $doing_it_wrong ) {
 			$this->setExpectedIncorrectUsage( 'wwo_update_script_type' );
@@ -214,6 +202,53 @@ public function test_update_script_types( Closure $set_up, string $expected, boo
 		$this->assertEquals( $expected, $actual );
 	}
 
+
+	/**
+	 * Test head and footer scripts.
+	 *
+	 * @covers ::wwo_update_script_type
+	 * @covers ::wwo_filter_print_scripts_array
+	 */
+	public function test_head_and_footer_scripts(): void {
+		wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', false );
+		wp_script_add_data( 'foo', 'worker', true );
+
+		$this->assertEquals(
+			$this->replace_placeholders( '{{ wwo_config }}{{ wwo_inline_script }}<script type="text/partytown" src="https://example.com/foo.js?ver=1.0.0" id="foo-js"  ></script>' ),
+			trim( get_echo( 'wp_print_head_scripts' ) )
+		);
+
+		wp_enqueue_script( 'bar', 'https://example.com/bar.js', array(), '1.0.0', true );
+		wp_script_add_data( 'bar', 'worker', true );
+
+		$this->assertEquals(
+			$this->replace_placeholders( '<script type="text/partytown" src="https://example.com/bar.js?ver=1.0.0" id="bar-js"  ></script>' ),
+			trim( get_echo( 'wp_print_footer_scripts' ) )
+		);
+	}
+
+	/**
+	 * Replace placeholders.
+	 *
+	 * @param string $template Template.
+	 * @return string Template with placeholders replaced.
+	 */
+	private function replace_placeholders( string $template ): string {
+		$wwo_config_data        = wp_scripts()->get_inline_script_data( 'web-worker-offloading', 'before' );
+		$wwo_inline_script_data = wp_scripts()->get_inline_script_data( 'web-worker-offloading', 'after' );
+
+		$template = str_replace(
+			'{{ wwo_config }}',
+			wp_get_inline_script_tag( $wwo_config_data, array( 'id' => 'web-worker-offloading-js-before' ) ),
+			$template
+		);
+		return str_replace(
+			'{{ wwo_inline_script }}',
+			wp_get_inline_script_tag( $wwo_inline_script_data, array( 'id' => 'web-worker-offloading-js-after' ) ),
+			$template
+		);
+	}
+
 	/**
 	 * Reset WP_Scripts and WP_Styles.
 	 */

From 6fb6553ba3c214482fd8e4001e4168c86af8c420 Mon Sep 17 00:00:00 2001
From: Weston Ruter <westonruter@google.com>
Date: Thu, 26 Sep 2024 15:14:35 -0700
Subject: [PATCH 10/13] Add tests for offloading script in head, footer, and
 both

---
 .../tests/test-web-worker-offloading.php      | 47 ++++++++++++++++++-
 1 file changed, 46 insertions(+), 1 deletion(-)

diff --git a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
index b2e614151d..8202e69e1a 100644
--- a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
+++ b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
@@ -202,7 +202,6 @@ public function test_update_script_types( Closure $set_up, string $expected, boo
 		$this->assertEquals( $expected, $actual );
 	}
 
-
 	/**
 	 * Test head and footer scripts.
 	 *
@@ -227,6 +226,52 @@ public function test_head_and_footer_scripts(): void {
 		);
 	}
 
+	/**
+	 * Test only head script.
+	 *
+	 * @covers ::wwo_update_script_type
+	 * @covers ::wwo_filter_print_scripts_array
+	 */
+	public function test_only_head_script(): void {
+		wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', false );
+		wp_script_add_data( 'foo', 'worker', true );
+
+		$this->assertEquals(
+			$this->replace_placeholders( '{{ wwo_config }}{{ wwo_inline_script }}<script type="text/partytown" src="https://example.com/foo.js?ver=1.0.0" id="foo-js"  ></script>' ),
+			trim( get_echo( 'wp_print_head_scripts' ) )
+		);
+
+		wp_enqueue_script( 'bar', 'https://example.com/bar.js', array(), '1.0.0', true );
+
+		$this->assertEquals(
+			$this->replace_placeholders( '<script src="https://example.com/bar.js?ver=1.0.0" id="bar-js"></script>' ),
+			trim( get_echo( 'wp_print_footer_scripts' ) )
+		);
+	}
+
+	/**
+	 * Test only footer script.
+	 *
+	 * @covers ::wwo_update_script_type
+	 * @covers ::wwo_filter_print_scripts_array
+	 */
+	public function test_only_footer_script(): void {
+		wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', false );
+
+		$this->assertEquals(
+			$this->replace_placeholders( '<script src="https://example.com/foo.js?ver=1.0.0" id="foo-js"></script>' ),
+			trim( get_echo( 'wp_print_head_scripts' ) )
+		);
+
+		wp_enqueue_script( 'bar', 'https://example.com/bar.js', array(), '1.0.0', true );
+		wp_script_add_data( 'bar', 'worker', true );
+
+		$this->assertEquals(
+			$this->replace_placeholders( '{{ wwo_config }}{{ wwo_inline_script }}<script type="text/partytown" src="https://example.com/bar.js?ver=1.0.0" id="bar-js"  ></script>' ),
+			trim( get_echo( 'wp_print_footer_scripts' ) )
+		);
+	}
+
 	/**
 	 * Replace placeholders.
 	 *

From bc843d58fc2a09269b997779a7a0ade481614177 Mon Sep 17 00:00:00 2001
From: Weston Ruter <westonruter@google.com>
Date: Thu, 26 Sep 2024 15:17:09 -0700
Subject: [PATCH 11/13] Account for truthy value for worker data key

---
 plugins/web-worker-offloading/hooks.php                         | 2 +-
 .../web-worker-offloading/tests/test-web-worker-offloading.php  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/plugins/web-worker-offloading/hooks.php b/plugins/web-worker-offloading/hooks.php
index b41cbf837b..146b900497 100644
--- a/plugins/web-worker-offloading/hooks.php
+++ b/plugins/web-worker-offloading/hooks.php
@@ -85,7 +85,7 @@ function wwo_register_default_scripts( WP_Scripts $scripts ): void {
 function wwo_filter_print_scripts_array( $to_do ): array {
 	$scripts = wp_scripts();
 	foreach ( (array) $to_do as $handle ) {
-		if ( true === $scripts->get_data( $handle, 'worker' ) ) {
+		if ( true === (bool) $scripts->get_data( $handle, 'worker' ) ) {
 			$scripts->set_group( 'web-worker-offloading', false, 0 ); // Try to print in the head.
 			array_unshift( $to_do, 'web-worker-offloading' );
 
diff --git a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
index 8202e69e1a..e13598d03b 100644
--- a/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
+++ b/plugins/web-worker-offloading/tests/test-web-worker-offloading.php
@@ -110,7 +110,7 @@ public static function data_update_script_types(): array {
 			'add-defer-script-for-web-worker-offloading' => array(
 				'set_up'         => static function (): void {
 					wp_enqueue_script( 'foo', 'https://example.com/foo.js', array(), '1.0.0', array( 'strategy' => 'defer' ) );
-					wp_script_add_data( 'foo', 'worker', true );
+					wp_script_add_data( 'foo', 'worker', 1 );
 				},
 				'expected'       => '{{ wwo_config }}{{ wwo_inline_script }}<script type="text/partytown" src="https://example.com/foo.js?ver=1.0.0" id="foo-js" defer data-wp-strategy="defer"></script>',
 				'doing_it_wrong' => false,

From 98929371d6fb6675123e883915c39a9e1ec4fa50 Mon Sep 17 00:00:00 2001
From: Weston Ruter <westonruter@google.com>
Date: Thu, 26 Sep 2024 15:27:04 -0700
Subject: [PATCH 12/13] Update readme

---
 plugins/web-worker-offloading/readme.txt | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/plugins/web-worker-offloading/readme.txt b/plugins/web-worker-offloading/readme.txt
index e1fb6f3fe3..774ff9139d 100644
--- a/plugins/web-worker-offloading/readme.txt
+++ b/plugins/web-worker-offloading/readme.txt
@@ -13,4 +13,15 @@ Offload JavaScript execution to a Web Worker.
 
 This plugin offloads JavaScript execution to a Web Worker, improving performance by freeing up the main thread.
 
-In order to opt-in a script to be loaded in a worker, simply add the `web-worker-offloading` script as a dependency.
+In order to opt-in a script to be loaded in a worker, simply add `worker` script data to a registered script. For example,
+if you have a script registered with the handle of `foo`, opt-in to offload it to a web worker by doing:
+
+`
+wp_script_add_data( 'foo', 'worker', true );
+`
+
+== Frequently Asked Questions ==
+
+= Why are my offloaded scripts not working and I see a 404 error in the console for `partytown-sandbox-sw.html`? =
+
+If you find that your offloaded scripts aren't working while also seeing a 404 error in the console for a file at `/wp-content/plugins/web-worker-offloading/build/partytown-sandbox-sw.html?1727389399791` then it's likely you have Chrome DevTools open with the "Bypass for Network" toggle enabled in the Application panel.

From bfb9e116a6c33cffbe729d5593e07448502ec1f2 Mon Sep 17 00:00:00 2001
From: Weston Ruter <westonruter@google.com>
Date: Fri, 27 Sep 2024 09:59:15 -0700
Subject: [PATCH 13/13] Revert param name change

---
 plugins/web-worker-offloading/hooks.php | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/plugins/web-worker-offloading/hooks.php b/plugins/web-worker-offloading/hooks.php
index 146b900497..d6ae5d9be4 100644
--- a/plugins/web-worker-offloading/hooks.php
+++ b/plugins/web-worker-offloading/hooks.php
@@ -79,15 +79,15 @@ function wwo_register_default_scripts( WP_Scripts $scripts ): void {
  *
  * @since 0.1.0
  *
- * @param string[]|mixed $to_do An array of enqueued script dependency handles.
+ * @param string[]|mixed $script_handles An array of enqueued script dependency handles.
  * @return string[] Script handles.
  */
-function wwo_filter_print_scripts_array( $to_do ): array {
+function wwo_filter_print_scripts_array( $script_handles ): array {
 	$scripts = wp_scripts();
-	foreach ( (array) $to_do as $handle ) {
+	foreach ( (array) $script_handles as $handle ) {
 		if ( true === (bool) $scripts->get_data( $handle, 'worker' ) ) {
 			$scripts->set_group( 'web-worker-offloading', false, 0 ); // Try to print in the head.
-			array_unshift( $to_do, 'web-worker-offloading' );
+			array_unshift( $script_handles, 'web-worker-offloading' );
 
 			// TODO: This should be reconsidered because scripts needing to be offloaded will often have after scripts. See <https://github.com/WordPress/performance/pull/1497/files#r1733538721>.
 			if ( false === wp_scripts()->get_data( $handle, 'strategy' ) ) {
@@ -96,7 +96,7 @@ function wwo_filter_print_scripts_array( $to_do ): array {
 			}
 		}
 	}
-	return $to_do;
+	return $script_handles;
 }
 add_filter( 'print_scripts_array', 'wwo_filter_print_scripts_array' );