bp_members_action_activate_account()

function bp_members_action_activate_account() {
	if ( ! bp_is_current_component( 'activate' ) ) {
		return;
	}

	if ( is_user_logged_in() ) {
		return;
	}

	if ( ! empty( $_POST['key'] ) ) {
		$key = wp_unslash( $_POST['key'] );

	// Backward compatibility with templates using `method="get"` in their activation forms.
	} elseif ( ! empty( $_GET['key'] ) ) {
		$key = wp_unslash( $_GET['key'] );
	}

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

	$bp = buddypress();

	/**
	 * Filters the activation signup.
	 *
	 * @since BuddyPress 1.1.0
	 *
	 * @param bool|int $value Value returned by activation.
	 *                        Integer on success, boolean on failure.
	 */
	$user = apply_filters( 'bp_core_activate_account', bp_core_activate_signup( $key ) );

	// If there were errors, add a message and redirect.
	if ( ! empty( $user->errors ) ) {
		bp_core_add_message( $user->get_error_message(), 'error' );
		bp_core_redirect( trailingslashit( bp_get_root_domain() . '/' . $bp->pages->activate->slug ) );
	}

	bp_core_add_message( __( 'Your account is now active!', 'buddyboss' ) );
	bp_core_redirect( add_query_arg( 'activated', '1', bp_get_activation_page() ) );

}