Display a table with available translation updates on the WordPress update screen

language-updates-table.php

<?php
/**
 * Plugin Name: Translation Updates Table
 *
 * @author Pascal Birchler <pascal@required.ch>
 * @license GPL2+
 */

/**
 * Displays a table with available translation updates.
 */
function required_language_updates_table() {
	$translation_updates = wp_get_translation_updates();

	if ( empty( $translation_updates ) ) {
		return;
	}

	require_once( ABSPATH . '/wp-admin/includes/translation-install.php' );

	$available_translations = wp_get_available_translations();
	$all_plugins            = get_plugins();
	?>
	<form method="post" action="<?php echo esc_url( 'update-core.php?action=do-translation-upgrade' ); ?>" name="upgrade-translations" class="upgrade">
		<table class="widefat" id="update-translations-table">
			<thead>
			<tr>
				<th scope="col" class="manage-column"><?php _e( 'Type' ); ?></th>
				<th scope="col" class="manage-column"><?php _e( 'Translation' ); ?></th>
			</tr>
			</thead>

			<tbody class="translations">
			<?php foreach ( $translation_updates as $available_update ) : ?>
				<?php
				$type     = $available_update->type;
				$language = $available_update->language;
				$slug     = $available_update->slug;

				if ( isset( $available_translations[ $language ] ) ) {
					$language = $available_translations[ $language ]['native_name'];
				}

				$name = '';

				if ( 'plugin' === $type ) {
					foreach ( $all_plugins as $plugin ) {
						if ( $slug === $plugin['TextDomain'] ) {
							$name = $plugin['Title'];
							break;
						}
					}
				} else if ( 'theme' === $type ) {
					$name = wp_get_theme( $slug )->get( 'Name' );
				}
				?>
				<tr>
					<td><p><?php echo esc_html( ucfirst( $type ) ); ?></p></td>
					<td>
						<p>
							<strong><?php echo esc_html( $language ); ?></strong>
							<?php if ( ! empty( $name ) ) : ?>
								<br>
								<?php echo esc_html( $name ); ?>
							<?php endif; ?>
						</p>
					</td>
				</tr>
			<?php endforeach; ?>
			</tbody>
		</table>
		<p><input class="button" type="submit" value="<?php esc_attr_e( 'Update Translations' ); ?>" name="upgrade"/>
		</p>
	</form>
	<?php
}

add_action( 'core_upgrade_preamble', 'required_language_updates_table' );