The first approach is to use a moving image to simulate the cursor.
This does not work well, so a second approach, involving static
cursors is provided. That requires a site administrator to precreate
all the cursors that can be used by a particular application set.
A warning message strongly suggests using a different browser as well.
This allows IE10 to function. Note that we would normally subclass
this type, but ArrayBuffer is implemented in native code, and so is
difficult to subclass.
