Background
Follow-up from T246419: Build collapsible sidebar and sidebar button .
Use cases
As a a reader, I would like my sidebar to be collapsed by default so that I can focus on the content of a page
As an editor, I would like my sidebar to be open by default so that I can easily go to pages related to my workflow, such as recent changes
Acceptance criteria
- Allow the sidebar default to vary based on logged-in status