@@ -110,9 +110,6 @@ function gutenberg_is_experiment_enabled( $name ) {
 require __DIR__ . '/compat/wordpress-7.0/kses.php';
 require __DIR__ . '/compat/wordpress-7.0/media.php';
 
-// Gutenberg plugin compat: disable client-side media processing by default.
-require __DIR__ . '/compat/plugin/media.php';
-
 // Experimental features.
 require __DIR__ . '/experimental/block-editor-settings-mobile.php';
 require __DIR__ . '/experimental/blocks.php';
 
@@ -96,11 +96,6 @@ function fail_if_died( $message ) {
 // Enable the widget block editor.
 tests_add_filter( 'gutenberg_use_widgets_block_editor', '__return_true' );
 
-// Enable client-side media processing for tests.
-// The Gutenberg plugin disables this by default (lib/compat/plugin/media.php),
-// but tests need the media functions to be loaded.
-tests_add_filter( 'wp_client_side_media_processing_enabled', '__return_true', 20 );
-
 // Start up the WP testing environment.
 require $_tests_dir . '/includes/bootstrap.php';
 
 
@@ -202,22 +202,18 @@ public function test_gutenberg_override_media_templates(): void {
 	}
 
 	/**
-	 * Tests that client-side media processing is disabled by default in the Gutenberg plugin.
-	 *
-	 * The core compat layer defaults to true, but the Gutenberg plugin
-	 * adds a filter to disable it by default (lib/compat/plugin/media.php)
-	 * until known issues are resolved.
+	 * Tests that client-side media processing is enabled by default in the Gutenberg plugin.
 	 *
 	 * @covers ::gutenberg_is_client_side_media_processing_enabled
 	 */
-	public function test_client_side_media_processing_disabled_by_default_in_plugin() {
+	public function test_client_side_media_processing_enabled_by_default_in_plugin() {
 		// Remove the test bootstrap override to check the plugin's actual default.
 		remove_filter( 'wp_client_side_media_processing_enabled', '__return_true', 20 );
 		$enabled = gutenberg_is_client_side_media_processing_enabled();
 		// Restore the test bootstrap override.
 		add_filter( 'wp_client_side_media_processing_enabled', '__return_true', 20 );
 
-		$this->assertFalse( $enabled );
+		$this->assertTrue( $enabled );
 	}
 
 	/**
 
@@ -35,10 +35,7 @@ test.use( {
 	},
 } );
 
-// Client-side media processing (and cross-origin isolation) is temporarily
-// disabled in the Gutenberg plugin. Skip until re-enabled.
-// See https://github.com/WordPress/gutenberg/pull/75756
-test.describe.skip( 'Cross-origin isolation', () => {
+test.describe( 'Cross-origin isolation', () => {
 	test.beforeEach( async ( { admin } ) => {
 		await admin.createNewPost();
 	} );