Cursor disappear

[jcubic]

Issue summary

When you have longer line then shorter line in CMD when moving cursor down from longer to shorter cursor disappear

Expected behavior

Cursor is at the end of the shorter line

Actual behavior

cursor disappear

Steps to reproduce

1. enter in cmd (you can use term.insert or term.set_command).

> foo bar baz
x

2. move cursor after baz in first line (you can click after first line)
3. press down arrow

[jcubic]

Also if there is 3rd longer line, it don't move to the second line it move to the 3rd. Should be easy to fix you need to check the line length before moving the cursor.