How to collapse all project nodes in a the netbeans projects window

When you have a lot of projects open in netbeans and edited a lot of
files, it is hard to navigate.

By pressing <Ctrl>-<1> you get to the project window and by typing you can move the selection.

To collapse all project nodes it is a little bit tricky. I found the solution in
this bugfix 113278.

You have to be in the projects-Windows by pressing <Ctrl>-<1>.

There you are not allowed to have something selected -> press <Ctrl>-<Space>.

Now In the context-menu ( get it by pressing <Shift>-<F10> ) and <UP>-<UP> you get to the "Collapes All" Context menu entry, which closes
all nodes in the projects-window.