The siderail, with multi-functionality (Board description, collapsible full-width, and soon category display via T92874: Display categories in Flow side rail), is not shown on Topic pages such as https://www.mediawiki.org/wiki/Topic:Si6ewcjhx7hvnybm
This has 2 major problems:

• Editors who go to the Topic page, will not have the context given in the description of the Board
• Editors cannot get the full-wdith view

Plus the smaller problem of inconsistent category location, although that might be fine in the original page-footer location on Topic pages.

See the example topic for some discussion. Suggested solutions include:

• Show all side rails [of the Boards a Topic is on] in chronological order
  • This, but only show the Original Board's siderail in full, and collapse the rest (individually)