typing chars to replace a multi-position selection in (empty) virtual space causes caret jump and split text

[glenn-slayden]

1. Create an empty document and enable virtual space in AvalonEdit.
2. Enter some text at the left margin

abc

3. Use <ctrl> with the mouse to select 3 empty positions in the space to the right of "abc":

...nevermind I mistakenly hit the button on this form in GitHub prematurely ... sorry