To hide the remaining time from assignment please add this css code in custom css. To do this please go to wp-admin -> Appearance -> Customize -> Custom CSS.
.assignment_timer {display:none !important;}
The editor is provided to send some text content in the assignment.
thank you.
1. The .assignment_timer didn't work...not sure what that's for, but this code did the trick for me, for anyone who needs this removed like I did: