"expand all" and "collapse all"

Is it possible to add a “expand all” and “collapse all” function?

You can expand and collapse the whole subtree starting from a root task using Ctrl+End and Ctrl+Home keyboard shortcuts.

Can I expand several root tasks at the same time?

It was supposed that select all + Ctrl+End would do it, however, it seems to be broken at the moment. I will look at this issue.