Form control question

[Handycam]

Probably a dumb question, but I notice I can tab to select menus on web forms. But once selected (highlighted) this way, how to I actually activate the menu, to make a selection in it with the keyboard?

[JKT]

Press the space bar.

Edit: It's a Full Keyboard Access feature and the space bar is the default action for selecting things that have the blue focus ring highlighting them in any dialogue or menu in any app.