Firebug Responsive Design Mode!

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Published: Jan 25, 2014
Written by Ted Lowe

Just discovered this feature...  simple nice way for testing responsive design from a desktop browser!

  1. Open Firebug (Inspect an element)
  2. Click 'Responsive Design Mode' toolbar button on right side:

 

Firefox's viewpoint changes to "mobile sized":

And voila! Test away!