Learning Path modules page not displaying

Problem/Motivation

When navigating to the Learnign Path inner-modules page to add activities to modules, the page is empty. The following code is present in opigno-learning-path-modules.html.twig:

{#<app-root class="d-block">{{ 'Loading app...'|t|e }}</app-root>#}

<div id="group-manager-app"></div>

Searching the codebase I can find nowhere where the app would be initialised on the #group-manager-app element. Reinstating the commented code fixes it.