When users do not have write access to the sys_user.time_zone field, visibility to it is lost on the form, too.
Steps to Reproduce
Impersonate the maint user.
Create an ACL with the following values:
- Name: sys_user.time_zone
- Operation: write
- Advanced: true
- Script: false
Impersonate any user without a role.
Click "My profile" under the avatar.
Note that the user is not able to see the value for the time zone field.
Give the user write access to the time_zone field.
Related Problem: PRB1273426