User has got the virtual_agent_admin role.
User can see the virtual agent designer module in the application navigator.
However, when user tries to access the designer, it just keeps on loading the page.
The modules don't load for the user.
London and above
This issue occurs when the user profile does not have a language set.
Below is a screenshot of what the user will see. You need to check with the browser console log.
The console log will show you errors ending with LANG=NUL
From the error in the browser it is trying to download a file that doesn't exist./scripts/convo-builder/thirdparty/intl/locales/NUL.jsx?v=07-14-2018_1223&. When checked in an OOB instance, the file name is /scripts/convo-builder/thirdparty/intl/locales/en.jsx?v=07-14-2018_1223&
Go to the user profile, and set the current user's language to English, and the designer will load as expected.