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Ok, we have transparent logos, so why not have a transparent background? Well here I will show you how to do it.

Before you get too exited, I'm going to tell you right now that this isn't perfect. It only looks transparent if you don't have any windows under firefox, and if the top right corner of your firefox window isn't in the top right corner of your screen, the "illusion" won't work. If you think up of a better way of doing it, tell me =].

Now if you want to see a screenshot of how it looks when you finish click here
Note that I was a few pixels off when cropping it =[.

First you will need to get a pixel ruler. I used this one.

Then you need to use the ruler to measure the top and bottom of your firefox while it is maximized, (whether or not you want to include the tab bar is up to you. If you choose to count the tab bar, the background will be distorted when you only have one tab open, and vice versa).

Click here and here.

After doing that, you need to take a screenshot of your desktop with all of your windows either closed, or minimized to the taskbar. To do this, hit the Prt Scrn button (usually on top of Insert and Delete). Then go to

Start -> All Programs -> Accessories -> Paint

Once you have opened paint hold Ctrl and press V to paste. Then save it somewhere. You will then need to edit that image so that you remove the amount of pixels that you measured from the top and bottom of your firefox, as well as the taskbar, from the top and bottom of your screen shot(this can also be done in Paint, but it is a little bit difficult...). I used Photoshop, and enabled the ruler Ctrl + R zoomed in to the top of my image until the ruler went in increments of one pixel, used the Rectangle Marquee tool, and went to Select -> Inverse Selection. Then cropped the image, by going to Image -> Crop. There are probably easier ways to do it, but I'm not a Photoshop genius =[.

Once you have done that, save your image, and use it as the background of your fastdial.

Again, like I said this isn't perfect, and could take a while, but its there for those who want to do it. =]