Getting a blank screen when opening Field Property in App Composer

Summary

Getting a blank screen when opening Field Property in App Composer

Content

Note: I was not facing this issue last week

Issue:
I had created a custom object and custom fields in that custom object last week

Now, I am trying to update the 'Required' property of that field, but when I click the Expression builder for the Required property, it throws up a blank screen. Nothing loads in that screen
This happens for all other properties of the field
It happens in all cases - whether there is an existing expression or if there is no expression
It also happens on custom fields of Standard objects