In Facebook photo comments, the bar is hidden and a scrollbar appears.

[ellotheth]

Overview

Facebook photos display in a lightbox-style container layered over the main
content. The photo comment thread is on the left side, with the area to add new
comments at the bottom of the thread (and the bottom of the lightbox). Clicking
in the 'Write a comment' area displays the monobar underneath its parent
container, and enables a scrollbar on the right.

Steps to reproduce

1. Visit Facebook.
2. Click on any photo from the news stream or timeline.
3. Click in the 'Write a comment...' text area on the bottom left.

Expected

The monobar appears below the text area, layered above its parent container.

Actual

The monobar appears below the text area, layered below its parent container,
and a scrollbar appears in the text area.