Source view editing bug, 10.0.x & 10.1.PRE.2

Source view editing bug, 10.0.x & 10.1.PRE.2

In source view, <shift-UParrow> and <shift-LTarrow>
seem to work as expected.

In source view, <shift-DNarrow> and <shift-RTarrow>
seem to mostly Not work. The highlighting stops
after one or a few lines.

Thank you,
Eddie Maddox
Inwood IA USA
greatnessguru@gmail.com