block.routing.yml

block_admin_block_delete:
  pattern: '/admin/structure/block/manage/{block}/delete'
  defaults:
    _entity_form: 'block.delete'
  requirements:
    _permission: 'administer blocks'

block_admin_edit:
  pattern: '/admin/structure/block/manage/{block}'
  defaults:
    _entity_form: 'block.default'
  requirements:
    _entity_access: 'block.update'

block_admin_display:
  pattern: '/admin/structure/block'
  defaults:
    _content: '\Drupal\block\Controller\BlockListController::listing'
    entity_type: 'block'
  requirements:
    _permission: 'administer blocks'

block_admin_add:
  pattern: '/admin/structure/block/add/{plugin_id}/{theme}'
  defaults:
    _content: '\Drupal\block\Controller\BlockAddController::blockAddConfigureForm'
  requirements:
    _permission: 'administer blocks'