Alt Text Editor for Images Missing a Description

add_action( 'admin_menu', function () {
    add_media_page( 'Alt Text Editor', 'Alt Text Editor', 'upload_files', 'wpide-alt-editor', function () {
        if ( isset( $_POST['wpide_alt'] ) && check_admin_referer( 'wpide_alt_editor' ) ) {
            $saved = 0;
            foreach ( (array) wp_unslash( $_POST['wpide_alt'] ) as $id => $alt ) {
                $id  = absint( $id );
                $alt = sanitize_text_field( $alt );
                if ( $id && '' !== $alt && current_user_can( 'edit_post', $id ) ) {
                    update_post_meta( $id, '_wp_attachment_image_alt', $alt );
                    $saved++;
                }
            }
            printf( '<div class="notice notice-success"><p>%s</p></div>', esc_html( sprintf( 'Saved alt text for %d image(s).', $saved ) ) );
        }

        $images = get_posts( array(
            'post_type'      => 'attachment',
            'post_mime_type' => 'image',
            'post_status'    => 'inherit',
            'posts_per_page' => 40,
            'no_found_rows'  => true,
            'meta_query'     => array(
                'relation' => 'OR',
                array( 'key' => '_wp_attachment_image_alt', 'compare' => 'NOT EXISTS' ),
                array( 'key' => '_wp_attachment_image_alt', 'value' => '' ),
            ),
        ) );

        echo '<div class="wrap"><h1>Alt Text Editor</h1>';
        if ( ! $images ) {
            echo '<p>Every image has alternative text.</p></div>';
            return;
        }
        echo '<p>Describe what each image shows or what it is for. Leave purely decorative images empty.</p><form method="post">';
        wp_nonce_field( 'wpide_alt_editor' );
        echo '<table class="widefat striped"><thead><tr><th style="width:110px">Image</th><th>Alt text</th></tr></thead><tbody>';
        foreach ( $images as $image ) {
            printf(
                '<tr><td>%1$s</td><td><label class="screen-reader-text" for="wpide-alt-%2$d">Alt text for %3$s</label><input type="text" class="large-text" id="wpide-alt-%2$d" name="wpide_alt[%2$d]" placeholder="%3$s"><p class="description">%4$s</p></td></tr>',
                wp_get_attachment_image( $image->ID, array( 96, 96 ) ),
                (int) $image->ID,
                esc_attr( $image->post_title ),
                esc_html( wp_basename( (string) get_attached_file( $image->ID ) ) )
            );
        }
        echo '</tbody></table>';
        submit_button( 'Save alt text' );
        echo '</form></div>';
    } );
} );