function bbp_edit_user_handler( $action = '' ) {

	// Bail if action is not `bbp-update-user`
	if ( 'bbp-update-user' !== $action ) {
		return;
	}

	// Bail if in wp-admin
	if ( is_admin() ) {
		return;
	}

	// Get the displayed user ID
	$user_id = bbp_get_displayed_user_id();

	// Nonce check
	if ( ! bbp_verify_nonce_request( 'update-user_' . $user_id ) ) {
		bbp_add_error( 'bbp_update_user_nonce', __( '<strong>ERROR</strong>: Are you sure you wanted to do that?', 'bbpress' ) );
		return;
	}

	// Cap check
	if ( ! current_user_can( 'edit_user', $user_id ) ) {
		bbp_add_error( 'bbp_update_user_capability', __( '<strong>ERROR</strong>: Are you sure you wanted to do that?', 'bbpress' ) );
		return;
	}

	// Empty email check
	if ( empty( $_POST['email'] ) ) {
		bbp_add_error( 'bbp_user_email_empty', __( '<strong>ERROR</strong>: That is not a valid email address.', 'bbpress' ), array( 'form-field' => 'email' ) );
		return;
	}

	// Get the users current email address to use for comparisons
	$user_email = bbp_get_displayed_user_field( 'user_email', 'raw' );

	// Bail if no email change
	if ( $user_email !== $_POST['email'] ) {

		// Check that new email address is valid
		if ( ! is_email( $_POST['email'] ) ) {
			bbp_add_error( 'bbp_user_email_invalid', __( '<strong>ERROR</strong>: That is not a valid email address.', 'bbpress' ), array( 'form-field' => 'email' ) );
			return;
		}

		// Check if email address is already in use
		if ( email_exists( $_POST['email'] ) ) {
			bbp_add_error( 'bbp_user_email_taken', __( '<strong>ERROR</strong>: That email address is already in use.', 'bbpress' ), array( 'form-field' => 'email' ) );
			return;
		}

		// Update the option
		$option = array(
			'hash'     => md5( $_POST['email'] . time() . wp_rand() ),
			'newemail' => $_POST['email'],
		);
		update_user_meta( $user_id, '_new_email', $option );

		// Attempt to notify the user of email address change
		bbp_edit_user_email_send_notification( $user_id, $option );

		// Set the POST email variable back to the user's email address
		// so `edit_user()` does not attempt to update it. This is not ideal,
		// but it's also what send_confirmation_on_profile_email() does.
		$_POST['email'] = $user_email;
	}

	// Do action based on who's profile you're editing
	$edit_action = bbp_is_user_home_edit()
		? 'personal_options_update'
		: 'edit_user_profile_update';

	do_action( $edit_action, $user_id );

	// Prevent edit_user() from wiping out the user's Toolbar on front setting
	if ( ! isset( $_POST['admin_bar_front'] ) && _get_admin_bar_pref( 'front', $user_id ) ) {
		$_POST['admin_bar_front'] = 1;
	}

	// Bail if errors already exist
	if ( bbp_has_errors() ) {
		return;
	}

	// Handle user edit
	$edit_user = edit_user( $user_id );

	// Error(s) editng the user, so copy them into the global
	if ( is_wp_error( $edit_user ) ) {
		bbpress()->errors = $edit_user;

	// Successful edit to redirect
	} elseif ( is_integer( $edit_user ) ) {

		// Maybe update super admin ability
		if ( is_multisite() && ! bbp_is_user_home_edit() && current_user_can( 'manage_network_options' ) && is_super_admin() ) {
			empty( $_POST['super_admin'] )
				? revoke_super_admin( $edit_user )
				: grant_super_admin( $edit_user );
		}

		// Redirect
		$args     = array( 'updated' => 'true' );
		$user_url = bbp_get_user_profile_edit_url( $edit_user );
		$redirect = add_query_arg( $args, $user_url );

		bbp_redirect( $redirect );
	}
}