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Criteria or check when we see the error "You are using an older version of firefox"

dimpi554
dimpi554
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Criteria or check when we see the error "You are using an older version of firefox that is no longer supported and may be insecure" on sites like facebook. Currently firefox 8.0 does not give this error but 3.5.4 does. What is the check performed by sites for this error?

Criteria or check when we see the error "You are using an older version of firefox that is no longer supported and may be insecure" on sites like facebook. Currently firefox 8.0 does not give this error but 3.5.4 does. What is the check performed by sites for this error?

All Replies (1)

the-edmeister
the-edmeister
  • Moderator
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Most web sites use the User Agent, which is sent in the header of the request for delivering the page. The user agent of the browser you used to post here is
Mozilla/5.0 (Windows NT 5.1; rv:18.0) Gecko/20100101 Firefox/18.0