public function setup_canonical_stack() {
		if ( ! bp_is_groups_component() ) {
			return;
		}

		if ( empty( $this->current_group ) ) {
			return;
		}

		/**
		 * Filters the default groups extension.
		 *
		 * @since 1.6.0
		 *
		 * @param string $value BP_GROUPS_DEFAULT_EXTENSION constant if defined,
		 *                      else 'home'.
		 */
		$this->default_extension = apply_filters( 'bp_groups_default_extension', defined( 'BP_GROUPS_DEFAULT_EXTENSION' ) ? BP_GROUPS_DEFAULT_EXTENSION : 'home' );

		$bp = buddypress();

		// If the activity component is not active and the current group has no custom front, members are displayed in the home nav.
		if ( 'members' === $this->default_extension && ! bp_is_active( 'activity' ) && ! $this->current_group->front_template ) {
			$this->default_extension = 'home';
		}

		if ( ! bp_current_action() ) {
			$bp->current_action = $this->default_extension;
		}

		// Prepare for a redirect to the canonical URL.
		$bp->canonical_stack['base_url'] = bp_get_group_permalink( $this->current_group );

		if ( bp_current_action() ) {
			$bp->canonical_stack['action'] = bp_current_action();
		}

		/**
		 * If there's no custom front.php template for the group, we need to make sure the canonical stack action
		 * is set to 'home' in these 2 cases:
		 *
		 * - the current action is 'activity' (eg: site.url/groups/single/activity) and the Activity component is active
		 * - the current action is 'members' (eg: site.url/groups/single/members) and the Activity component is *not* active.
		 */
		if ( ! $this->current_group->front_template && ( bp_is_current_action( 'activity' ) || ( ! bp_is_active( 'activity' ) && bp_is_current_action( 'members' ) ) ) ) {
			$bp->canonical_stack['action'] = 'home';
		}

		if ( ! empty( $bp->action_variables ) ) {
			$bp->canonical_stack['action_variables'] = bp_action_variables();
		}

		// When viewing the default extension, the canonical URL should not have
		// that extension's slug, unless more has been tacked onto the URL via
		// action variables.
		if ( bp_is_current_action( $this->default_extension ) && empty( $bp->action_variables ) )  {
			unset( $bp->canonical_stack['action'] );
		}
	}