By tim.plunkett on
Change record status: 
Published (View all published change records)
Project: 
Drupal core
Introduced in branch: 
8.x
Issue links: 
https://www.drupal.org/node/2084197
Description: 

Previously there was a distinction in the menu-block integration between system-provided menus and custom menus.
The five system menus (tools, admin, user, main, footer) were addressed with a plugin ID prefixed with system_menu_block:menu-

system_menu_block:menu-tools
system_menu_block:menu-admin

Any custom menus created via the Menu UI were given a separate plugin ID prefix of menu_menu_block:

menu_menu_block:my_awesome_menu
menu_menu_block:my_second_favorite_one

Now in Drupal 8, there is only one single prefix: system_menu_block:, the menu- portion is dropped:

system_menu_block:tools
system_menu_block:admin
system_menu_block:my_awesome_menu
system_menu_block:my_second_favorite_one
Impacts: 
Module developers
Updates Done (doc team, etc.)
Online documentation: 
Not done
Theming guide: 
Not done
Module developer documentation: 
Not done
Examples project: 
Not done
Coder Review: 
Not done
Coder Upgrade: 
Not done
Other: 
Other updates done