Updated Drupal to 8.6. This goes with the following updates because it's possible...

[yaffs-website] / web / core / profiles / demo_umami / config / install / block.block.seven_page_title.yml

langcode: en
status: true
dependencies:
  theme:
    - seven
id: seven_page_title
theme: seven
region: header
weight: -30
provider: null
plugin: page_title_block
settings:
  id: page_title_block
  label: 'Page title'
  provider: core
  label_display: '0'
visibility: {  }