Each page contains a page-specific tool bar with commands for the current page.
Page tool bars vary in options but some options are consistent among pages, such as menu.
See Page Tool Bar Icons.
Instead of displaying an menu, the page tool bar may display action buttons instead, such as Create New, View Reference, Subscribe to, and more.
If a page tool bar function is grayed out, it is inactive because no items have been selected on the page, or the page does not have any items on it.
Some actions are only available to users with certain project roles.
If you believe a function is missing, contact your project owner or lead(s).