Remove current action or filter from plugin

gistfile1.txt

<?php
/**
 * Remove current action or filter from plugin
 *
 * @param string $class_name Class name enqueueing the action.
 * @param null   $action_name Action name.
 */
function remove_plugin_action( $class_name, $action_name = null ) {
	global $wp_filter;

	if ( null === $action_name ) {
		$action_name = current_action();
	}

	/** @var WP_Hook $hooks WP hooks. */
	$hooks = $wp_filter[ $action_name ];

	$callbacks = $hooks->callbacks;

	foreach ( $callbacks as $priority => $actions ) {
		foreach ( $actions as $action ) {
			$function = $action['function'];
			if ( is_array( $function ) ) {
				$callback = $function[0];
				if (
					( is_object( $callback ) && get_class( $callback ) === $class_name ) ||
					( is_string( $callback ) && $callback === $class_name )
				) {
					remove_action( $action_name, $function, $priority );
				}
			}
		}
	}
}

// Example of usage.

/**
 * Enqueue Google maps scripts only on certain pages.
 */
function action_google_maps_script() {
	if ( ! ( is_page_template( 'templ-contact.php' ) ) ) {
		remove_plugin_action( 'PageSpeed_Optimization' );
	}
}

add_action( 'wp_enqueue_scripts', 'action_google_maps_script', 0 );