Editor not working well when using Firefox.

[ejvalmores]

I tried deleting the entire default content (select all then delete) in an attempt to start writing something from scratch. Editor seems to no longer work properly when I do.
Please see the video link:
http://www.screencast.com/t/tXqSBPGG

Note:
Editor works well with Safari and Chrome. Only Firefox seems to have this issue so far. (haven't tested in IE yet).

Thanks!

Cheers!