anchor.diff:  The todoapp uses this feature so that different users' list of todo items are kept separate from one another.
   A user with administrator is able to switch their own "tenancy" to the tenancy of some other user, in order to access the objects in that tenancy:
   
  -image::https://raw.githubusercontent.com/apache/isis/master/antora/toc/modules/ROOT/images/what-is-apache-isis/isis-in-pictures/160-switch-tenancy.png[link="https://raw.githubusercontent.com/apache/isis/master/antora/toc/modules/ROOT/images/what-is-apache-isis/isis-in-pictures/160-switch-tenancy.png"]
  +image::https://raw.githubusercontent.com/apache/isis/master/antora/components/docs/modules/ROOT/images/what-is-apache-isis/isis-in-pictures/160-switch-tenancy.png[link="https://raw.githubusercontent.com/apache/isis/master/antora/components/docs/modules/ROOT/images/what-is-apache-isis/isis-in-pictures/160-switch-tenancy.png"]
   
   For more details, see the security module's link:https://platform.incode.org/modules/spi/security/spi-security.html[README] (or xref:security:ROOT:about.adoc[SecMan extension])..
   
  
positive.code: By default properties on domain entities are editable, meaning they can be changed directly.
  In the todoapp example, the `ToDoItem`'s description is one such editable property:
  
  image::https://raw.githubusercontent.com/apache/isis/master/antora/toc/modules/ROOT/images/what-is-apache-isis/isis-in-pictures/050-edit-property.png[link="https://raw.githubusercontent.com/apache/isis/master/antora/toc/modules/ROOT/images/what-is-apache-isis/isis-in-pictures/050-edit-property.png"]
  
  Note that some of the properties are read-only even in edit mode; individual properties can be made non-editable.
  It is also possible to make all properties disabled and thus enforce changes only through actions (below).
  
negative.code: The core framework supports file-based realms, while the xref:security:ROOT:about.adoc[SecMan extension] provides a well-features subdomain of users, roles and permissions against features derived from the Apache Isis metamodel.
  
  
  image::https://raw.githubusercontent.com/apache/isis/master/antora/components/docs/modules/ROOT/images/what-is-apache-isis/isis-in-pictures/010-login.png[link="https://raw.githubusercontent.com/apache/isis/master/antora/components/docs/modules/ROOT/images/what-is-apache-isis/isis-in-pictures/010-login.png"]
  
  
  === Install Fixtures
  