Resize datum in all views
Resize datum in a specific view only
Notice that there is a control titled 3D that displays at the ends of the datum. With the 3D designation, the datum is in Model Extent mode. This means that if you drag the control to resize the datum extent, it changes the extent of that datum in all other parallel views, provided those datums also have the 3D model extent control.
Model extent control
View-specific extent control
If you drag a datum extent outside the crop boundary of the view, the control on the extent is always in view-specific (2D) mode. You also cannot propagate its extents to other views.
If you move the 2D control of a datum on top of a 3D control, the 2D control becomes a 3D control.