public static function check_content_for_popups( $content ) {

		// Only search for popups in the main query of a singular page.
		if ( is_singular() && in_the_loop() && is_main_query() ) {
			/**
			 * We want to detect instances of popmake-### but only within classes and not in the actual text.
			 * So, we check to make sure it is wrapped by quotes to make sure it's in the class="" attribute
			 * but also allow for whitespace and characters in case there are classes before or after it.
			 */
			preg_match_all( '/[\'\"][\s\w\-\_]*?popmake-(\d+)[\s\w\-\_]*?[\'\"]/', $content, $matches );

			// Then, if we find any popups, let's preload it.
			foreach ( $matches[1] as $popup_id ) {
				self::preload_popup_by_id_if_enabled( $popup_id );
			}
		}

		return $content;
	}