How do I scroll a page up or down in library grid mode on second display (shortcut wo

I am using two displays, teh primary shows the develop module and the secondary the library module in grid mode. I would like to be able to scroll the grid a page at a time but the keystroke for this does not work on the second display.

If I use a single display in library grid mode i can scroll a page at a time either up or down using Function Up/Down keystroke on my keyboard.

Is this function unavailable when using a second monitor or am I missing something?

I understand that for most shortcuts on a second display you use teh shift ket in combination with teh normal shortcut, this does not work for my particular requirement.