It is now possible to include collapsible wiki pages and tasks in your wiki pages. The collapsible item behaves like the collapsed one, but when page is shown it will appear expanded by default.
To make your inclusion collapsible, add collapsible parameter:
{{Other_Page|collapsible}}
{{Task:4321|collapsible}}
Here's how collapsible inclusions look like:
Expanded (by default):
Collapsed:
