field_ui_field_edit_form in core/modules/field_ui/field_ui.admin.inc

Form constructor for the field instance settings form.

file_settings_form in core/modules/file/file.admin.inc

Form callback for file settings.

link_field_instance_settings_form in core/modules/link/link.module

Implements hook_field_instance_settings_form().

path_patterns_form in core/modules/path/path.admin.inc

Form builder; Configure the URL alias patterns.

system_site_maintenance_mode in core/modules/system/system.admin.inc

Form builder; Configure the site's maintenance status.

user_settings_email in core/modules/user/user.admin.inc

Form builder; Configure user email settings for this site.