Overview window opens in the background

Created by: ghost

Steps to reproduce:

1. Open an Iceweasel/Firefox window and maximize it
2. Click on Show Overview in Hamster GNOME Shell extension

Result: A notification appears saying: Time Tracker, January 11-17 2016 is ready; Hamster Overview window stays in the background.

Expected result: Hamster Overview window appears in the foreground.

I'm using the following versions:

• GNOME 3.18.2
• hamster-time-tracker 1.04-2
• hamster-shell-extension-git 20151020.g030fb5a-1