Egg No -1:

Open Firefox browser. Click on the address bar and type “about:mozilla” (without quotes) and hit enter.

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You get a red colour screen with the quote:
“Mammon slept. And the beast reborn spread over the earth and its numbers grew legion. And they proclaimed the times and sacrificed crops unto the fire, with the cunning of foxes. And they built a new world in their own image as promised by the sacred words, and spoke of the beast with their children. Mammon awoke, and lo! it was naught but a follower.”
from The Book of Mozilla, 11:9 (10th Edition)

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Egg No-2:

Open Firefox browser.
Enter the following in the address bar:

chrome://browser/content/browser.xul

press enter. What you can see is “Firefox within Firefox”. You get as many browsers within browser, as many times you type the code and press enter.

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