IE11: Unable to maintain Selection direction when the text is selected from right to left

[avcs06]

When user starts selecting multiple characters using SHIFT + LEFT ARROW, the position calculator inserts a span to calculate the position and preserves the previous Selection by re-applying the selection after position calculation, but in IE11 I am not able to maintain the selection direction. Resulting in the behavior: a fresh selection starts at the position discarding the previous selection.

Selection.setBaseAndExtent or Selection.extend can be used to retain the selection direction but unfortunately both of them doesn't work in IE11. Any suggestions on how to resolve this problem will be appreciated.