Ann is correct ... and "Global Fx Mute" can be added to your Program monitor controls (as Ann shows) by going into the + menu on the Program monitor, and dragging that particular icon onto your Program Monitor control block. And that's a toggle control, click it 'blue', it's active. Click again it's gray, your effects are back.
You can also go to the Keyboard shortcuts dialog (Ctrl/Cmd-K) and type "Global" in the search box, and then go down to the keyboard shortcut and assign it one if it doesn't already have one. And toggle via the keyboard.