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CloseReview for User Agent Switcher by Jimmy Page
Rated 3 out of 5 stars
I would give this one or two more stars apart from one unforgivable problem. It disables the ability to type in the console in firebug. Someone else has noticed this here https://groups.google.com/forum/?fromgroups=#!topic/firebug/4GyC6_2prRQ . Apart from that really well written.
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