Seven Sub-theme shows Branding and Nav instead of Local Tasks / Admin Menu [8] My client wants some basic changes to the Drupal admin pages (yay!) so I'm trying to create a sub-theme of the core seven theme.  I have my sub theme working and my css is being loaded, but the local admin menu normally shown in the header of the seven theme had been replaced by the branding block and main navigation from normal pages.

Here is my info.yml file :

name: My Admin
type: theme
description: A sub-theme of the seven admin theme.
core: 8.x
base theme: seven

libraries:
  - my_admin/global-styling


and libraries.yml :

global-styling:
  css:
    component:
      css/style.css: {}


I've tried copying seven.theme file to my sub-theme folder and renaming the functions with my theme name (which has an underscore), but no love there. Any ideas how to do this properly ?
I think you need to copy the regions as well.  Here's the YML from our custom Admin theme.

name: MY Admin Theme
type: theme
description: 'My administration theme'
core: 8.x
base theme: seven
libraries:
  - my_admin/global-styling

regions:
  header: 'Header'
  pre_content: 'Pre-content'
  breadcrumb: Breadcrumb
  highlighted: Highlighted
  help: Help
  content: Content
  page_top: 'Page top'
  page_bottom: 'Page bottom'
  sidebar_first: 'First sidebar'

ckeditor_stylesheets:
  - ../main_theme/css/style.css