[Paraview] Selecting multiple points with "Select points through"

[David Doria]

If I use the "select points on" tool, I can select a point, then
release the mouse, hold control, select the "select points on" tool
again, select another point, and they will now both be in the
selection.

However, if I try to do this with the "select points through" tool,
the selection is simply replaced instead of appended.

Is this the expected behavior?

Thanks,

David