Install the Firefox OS desktop build

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Firefox OS Simulator is an add-on for the Firefox browser allowing you to run Mozilla's new operating system directly from your browser. You don't need to get your hands on a new mobile phone to get a glimpse of the Firefox OS, all you require to get started, is a PC connected to the internet and the Firefox web-browser!


  • When prompted, click on the Install button.

First launch

  • Once installed you can launch Firefox OS Simulator using the below method:
  • Click on the Firefox button > Web Developer > Firefox OS Simulator
  • Turn the simulator on.
  • Firefox OS shall open in a new window:

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