Accessibility: Post textbox does not read characters when reviewing with arrow keys

Customer report:

"i cannot see in braille what i am typing, nor is JAWS able to speak it."
"From my own user perspective, the only show stopper I see would be not being able to read in braille, or hear with speech what is being written in the message window."

Repro:
1. Type some characters in the message input box
2. Use the arrow keys to move back and forth through the text

Observed: no read out of characters
Expected: Characters are read when arrowing through them and text can be reviewed with INSERT+5, INSERT+8

Note: This should apply to the RHS and main message input fileds