Sometimes, the module.js and clientlib.js was not loaded properly and it make the View members of group function not work.

I struggled to reproduce this in standard Moodle:

1. Go to qa.moodle.net, and log in as manager.
2. Open Developer Tool in browser (Ex: Chrome or Firefox) and switch to Console tab
3. Go to any course (Ex: Activity examples)
4. Go to Users -> Groups
5. Check the error log on Console tab
6. Try to click on Group B (1)

Expected result: 

• Javascript will loaded without error
• When clicked on Group B (1), the members of that group will show

Actual result:

• Console tab throw error
• Javascript was not loaded properly
• View members not worked

Reason: In index.mustache file have one part of script called init_index and groupslist and sometime it was called before require->js in index.php

Pls check attachments for more details