Updated Drupal to 8.6. This goes with the following updates because it's possible...
[yaffs-website] / web / core / modules / user / migrations / user_profile_field_instance.yml
1 id: user_profile_field_instance
2 label: User profile field instance configuration
3 migration_tags:
4   - Drupal 6
5   - Drupal 7
6   - Configuration
7 source:
8   plugin: profile_field
9   constants:
10     entity_type: user
11     bundle: user
12 process:
13   entity_type: 'constants/entity_type'
14   bundle: 'constants/bundle'
15   label: title
16   description: explanation
17   field_name:
18     -
19       plugin: migration_lookup
20       migration: user_profile_field
21       source: fid
22     -
23       plugin: skip_on_empty
24       method: row
25     -
26       plugin: extract
27       index:
28         - 1
29   required: required
30 destination:
31   plugin: entity:field_config
32 migration_dependencies:
33   required:
34     - user_profile_field