I went to /user/profile/index.php and tried to add a date/time field then immediately clicked the button next to it out of habit (which actually creates a category.

I clicked back but now date/time is already selected. I changed it to "create a new profile field" intending it then select date/time but the page moved. The following page displayed the below.

Warning: require_once(/home/andrew/Desktop/code/moodle/int/master/user/profile/field//define.class.php): failed to open stream: No such file or directory in /home/andrew/Desktop/code/moodle/int/master/user/profile/index_field_form.php on line 21
Call Stack

1. Time Memory Function Location
   1 0.0018 309176 {main}( ) ../index.php:0
   2 1.5117 44452816 profile_edit_field( ) ../index.php:74
   3 1.5138 44533320 moodleform->moodleform( ) ../definelib.php:478
   4 1.5170 44549040 field_form->definition( ) ../formslib.php:191
   
   ( ! ) Fatal error: require_once(): Failed opening required '/home/andrew/Desktop/code/moodle/int/master/user/profile/field//define.class.php' (include_path='/home/andrew/Desktop/code/moodle/int/master/lib/zend:/home/andrew/Desktop/code/moodle/int/master/lib/pear:.:/usr/share/php:/usr/share/pear') in /home/andrew/Desktop/code/moodle/int/master/user/profile/index_field_form.php on line 21
   Call Stack
   # Time Memory Function Location
   1 0.0018 309176 {main}

   ( ) ../index.php:0
   2 1.5117 44452816 profile_edit_field( ) ../index.php:74
   3 1.5138 44533320 moodleform->moodleform( ) ../definelib.php:478
   4 1.5170 44549040 field_form->definition( ) ../formslib.php:191