Please update the following pages in the docs:

* [ ] [https://www.openproject.org/docs/user-guide/backlogs-scrum/](https://www.openproject.org/docs/user-guide/backlogs-scrum/) including all-subpages
* [ ] [https://www.openproject.org/docs/user-guide/projects/project-settings/backlogs-settings/](https://www.openproject.org/docs/user-guide/projects/project-settings/backlogs-settings/) 
* Begin of the insertion[x]End of the insertion Begin of the deletion [ ]End of the deletion [https://www.openproject.org/docs/system-admin-guide/backlogs/](https://www.openproject.org/docs/system-admin-guide/backlogs/)