Add Performant Translations

src/wp-admin/includes/plugin.php

@@ -1009,6 +1009,7 @@ function delete_plugins( $plugins, $deprecated = '' ) {
 			foreach ( $translations as $translation => $data ) {
 				$wp_filesystem->delete( WP_LANG_DIR . '/plugins/' . $plugin_slug . '-' . $translation . '.po' );
 				$wp_filesystem->delete( WP_LANG_DIR . '/plugins/' . $plugin_slug . '-' . $translation . '.mo' );
+				$wp_filesystem->delete( WP_LANG_DIR . '/plugins/' . $plugin_slug . '-' . $translation . '.mo.php' );
 
 				$json_translation_files = glob( WP_LANG_DIR . '/plugins/' . $plugin_slug . '-' . $translation . '-*.json' );
 				if ( $json_translation_files ) {

src/wp-includes/class-wp-locale-switcher.php

@@ -283,6 +283,8 @@ private function change_locale( $locale ) {
 
 		$wp_locale = new WP_Locale();
 
+		WP_Translation_Controller::instance()->set_locale( $locale );
+
 		/**
 		 * Fires when the locale is switched to or restored.
 		 *

src/wp-includes/compat.php

@@ -497,3 +497,35 @@ function str_ends_with( $haystack, $needle ) {
 if ( ! defined( 'IMG_WEBP' ) ) {
 	define( 'IMG_WEBP', IMAGETYPE_WEBP );
 }
+
+if ( ! function_exists( 'array_is_list' ) ) {
+	/**
+	 * Polyfill for `array_is_list()` function added in PHP 8.1.
+	 *
+	 * Determines if the given array is a list.
+	 *
+	 * An array is considered a list if its keys consist of consecutive numbers from 0 to count($array)-1.
+	 *
+	 * @see https://github.com/symfony/polyfill-php81/tree/main
+	 *
+	 * @since 6.5.0
+	 *
+	 * @param array<mixed> $arr The array being evaluated.
+	 * @return bool True if array is a list, false otherwise.
+	 */
+	function array_is_list( $arr ) {
+		if ( ( array() === $arr ) || ( array_values( $arr ) === $arr ) ) {
+			return true;
+		}
+
+		$next_key = -1;
+
+		foreach ( $arr as $k => $v ) {
+			if ( ++$next_key !== $k ) {
+				return false;
+			}
+		}
+
+		return true;
+	}
+}

src/wp-includes/functions.php

@@ -6533,7 +6533,7 @@ function wp_timezone_choice( $selected_zone, $locale = null ) {
 	if ( ! $mo_loaded || $locale !== $locale_loaded ) {
 		$locale_loaded = $locale ? $locale : get_locale();
 		$mofile        = WP_LANG_DIR . '/continents-cities-' . $locale_loaded . '.mo';
-		unload_textdomain( 'continents-cities' );
+		unload_textdomain( 'continents-cities', true );
 		load_textdomain( 'continents-cities', $mofile, $locale_loaded );
 		$mo_loaded = true;
 	}