Alert Window size?

So got a bit of a question

Up until this morning, I was using Firefox 28, because I was not at all fond of the Firefox 29+ setup. The stability issues have become too great however, so I updated to the current Firefox as of now. However, I noticed something a little annoying.

In the pre-FF29 Firefox X-notifier setup, the alert window whenever I received an email would show up in the lower right corner of the screen. It was small and compact but still noticeable enough. Upon updating to the current Firefox however, the alert window has been increased to an obnoxiously large size, to the point it impedes activity by covering up whatever I might be clicking on while working.

Is there any way to adjust the alert window size possibly back to its more convenient size? I can't figure out if it's a problem caused by the extension or by Firefox itself, I don't really know.