Add an ID to a tab?

@gwmbox

UM is using a lot of filter hooks where you can modify the output without hacking UM and there must be a hook available where you want to insert your ID.

https://docs.ultimatemember.com/article/1785-um-hooks-map

@gwmbox

Your hooks are all in this template file
.../plugins/ultimate-member/templates/profile.php

https://docs.ultimatemember.com/article/1516-templates-map

@gwmbox

You can try to use this filter um_profile_menu_link_{$id} in
../plugins/ultimate-member/includes/core/um-actions-profile.php
at line 1726

where you can get the value for $id from
<div class="um-profile-nav-item um-profile-nav-<?php echo esc_attr( $id . ' ' . $profile_nav_class ); ?>">

/**
 * UM hook
 *
 * @type filter
 * @title um_profile_menu_link_{$id}
 * @description Change profile menu link by tab $id
 * @input_vars
 * [{"var":"$nav_link","type":"string","desc":"Profile Tab Link"}]
 * @change_log
 * ["Since: 2.0"]
 * @usage
 * <?php add_filter( 'um_profile_menu_link_{$id}', 'function_name', 10, 1 ); ?>
 * @example
 * <?php
 * add_filter( 'um_profile_menu_link_{$id}', 'my_profile_menu_link', 10, 1 );
 * function my_profile_menu_link( $nav_link ) {
 *     // your code here
 *     return $nav_link;
 * }
 * ?>
 */