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firefox doesn't respect 304 http status code

  • 2 replies
  • 1 has this problem
  • 3 views
  • Last reply by mehdyhaghy

mehdyhaghy
mehdyhaghy
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I have a performance issue with our website in firefox, the problem is firefox transfers files when server send 304 response. on a heavy page like ours, this will cause firefox to transmit 8 KB of javascript while chrome downloads only 196 Bytes. the difference is drastic on pages which heavily use javascript libraries, when users refresh the page.

sample url  : https://cdt.irslogics.com/Scripts/common.js?v=1.03

screenshots of reload url (304 status code) in firefox and chrome: https://ibb.co/dZaAKa https://ibb.co/mbQXXv

I have a performance issue with our website in firefox, the problem is firefox transfers files when server send 304 response. on a heavy page like ours, this will cause firefox to transmit 8 KB of javascript while chrome downloads only 196 Bytes. the difference is drastic on pages which heavily use javascript libraries, when users refresh the page. sample url : https://cdt.irslogics.com/Scripts/common.js?v=1.03 screenshots of reload url (304 status code) in firefox and chrome: https://ibb.co/dZaAKa https://ibb.co/mbQXXv

All Replies (2)

Shadow110
Shadow110
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If that URL is used when run through http://www.jslint.com/ it fails with errors.

Have you run the code through this : https://developers.google.com/closure/compiler/?csw=1

What about the html is it set up for the 304 error ?

Please let us know if this solved your issue or if need further assistance.

mehdyhaghy
mehdyhaghy Question owner
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304 is not an error, it's "Not Modified" http status code sent from server to avoid transmission of cached files.

above file is just a sample file to show the transfer issue. you can basically test this on any html page with large js files. load the page, refresh it again and check transfer size for files with status 304.