Forms: Fix boot script timing with third-party plugins that use script modules

projects/packages/forms/changelog/fix-forms-boot-importmap-compat

@@ -0,0 +1,4 @@
+Significance: patch
+Type: fixed
+
+Fix Forms dashboard black screen when The Events Calendar is active by replacing fragile import() in inline script with a proper script module.

projects/packages/forms/src/dashboard/class-dashboard.php

@@ -59,6 +59,66 @@ public static function load_wp_build() {
 		}
 	}
 
+	/**
+	 * Fix import map ordering for the wp-build boot script.
+	 *
+	 * In wp-admin, _wp_footer_scripts (classic scripts) and print_import_map
+	 * both hook into admin_print_footer_scripts at priority 10, but
+	 * _wp_footer_scripts is registered first. This causes the inline
+	 * import("@wordpress/boot") to execute before the import map exists.
+	 *
+	 * This fix moves the import() call from the classic inline script to a
+	 * <script type="module"> printed at priority 20 (after the import map).
+	 *
+	 * @todo Remove once @wordpress/build ships with the loader.js fix upstream
+	 *       (WordPress/gutenberg#76870) and Jetpack updates the dependency.
+	 */
+	public static function fix_boot_import_map_ordering() {
+		$handle = self::FORMS_WPBUILD_ADMIN_SLUG . '-prerequisites';
+
+		add_action(
+			'admin_enqueue_scripts',
+			static function () use ( $handle ) {
+				if ( ! Dashboard::is_jetpack_forms_admin_page() ) {
+					return;
+				}
+
+				$data = wp_scripts()->get_data( $handle, 'after' );
+				if ( empty( $data ) ) {
+					return;
+				}
+
+				// Find and extract the import("@wordpress/boot") inline script.
+				$boot_script = null;
+				$remaining   = array();
+				foreach ( $data as $line ) {
+					if ( strpos( $line, '@wordpress/boot' ) !== false ) {
+						$boot_script = $line;
+					} else {
+						$remaining[] = $line;
+					}
+				}
+
+				if ( $boot_script === null ) {
+					return;
+				}
+
+				// Remove from the classic script handle.
+				wp_scripts()->add_data( $handle, 'after', $remaining );
+
+				// Re-emit as a module script after the import map.
+				add_action(
+					'admin_print_footer_scripts',
+					static function () use ( $boot_script ) {
+						wp_print_inline_script_tag( $boot_script, array( 'type' => 'module' ) );
+					},
+					20
+				);
+			},
+			PHP_INT_MAX
+		);
+	}
+
 	/**
 	 * Script handle for the JS file we enqueue in the Feedback admin page.
 	 *
@@ -97,6 +157,7 @@ public function init() {
 
 		if ( $is_wp_build_enabled ) {
 			self::load_wp_build();
+			self::fix_boot_import_map_ordering();
 		}
 
 		add_action( 'admin_enqueue_scripts', array( $this, 'load_admin_scripts' ) );