Comment 10 for bug 744325

After some more experimentation I've found a way to reproduce. While its not 100% it does happen quite frequently.

I use thunderbird as my mailer, and when maximized I noticed when I went to drag email into a folder if I went too fast the launcher would pop out. When that happened 90% of the time I would notice and pull back. However if I didn't and the drag went into the launcher area when it appeared it would get stuck in the unresponsive state.

Also I noticed sometimes its appears quite random as to what mouse motions cause the launcher to become visible. Sometimes its just moving the cursor to the left side of the screen. Other times I have to go to the top left corner to make it become invisible. The later case seems to happen after I use the workaround in comment #9 to reset the launcher.