When a form is loading, it sometimes hangs and shows a spinning wheel.
If we go back to previous page and open it again, it will work.

In F12 Developer Tools, we can see this error
Uncaught TypeError: Mscrm.TurboForm.Control.CustomScriptsManager.$1g.contentWindow[$v_0.$77_1] is not a function

We tried to use 'Legacy Form Rendering', but it did NOT fix the issue.


These is another similar issue here, https://connect.microsoft.com/dynamicssuggestions/Feedback/Details/1656982