Track View > Curve Editor or Dope Sheet > Navigation: Track View toolbar > Pan
With Pan you can click and drag the Key window to move it left, right, up or down. Pan remains active until you right-click to cancel or click another option. The Pan button is yellow while active.
If you have a middle mouse button, pressing it will instantly give you the Pan capability in Track View, as in the rest of the software.
Drag horizontally in all modes to slide the view forward and backward in time. Drag vertically to slide the view up and down in value.