Of course you can also play with his unicorn Firefox. Let's see how….
Step 1. First, open it Firefox. Click the hamburger menu (the three horizontal bars) in the upper right, then click "Customize".
Step 2. In the "Customize" tab Firefox, you will see a list of available items for configuring the toolbar. Click and drag all the toolbar items to the right of the "Overflow Menu" except the "Flexible Space".
Step 3. At the bottom of the window will appear the button "Unicorn”(Unicorn). Click on it.
Step 4. A press type will appear on the left side of the tab Pong with a small unicorn icon. In this version of the game, the "Flexible Space" box serves as a racket Pong, and the unicorn icon is the ball.
To play, just use the left and right arrow keys on your keyboard to move the UP flexible space so that the unicorn does not pass through it. The lower packages Pong it is operated automatically by the game.
If you lose and want to play again, just double-click the button Unicorn.
When the game is finished, click "Reset Defaults" to restore all the items you went to in the Popup menu with Step 2.