Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Why Firefox 27 wrongly renders pages with www. prefix in URL while all is fine if page is addressed without www. prefix ?

  • 6 replies
  • 3 have this problem
  • 20 views
  • Last reply by cor-el

more options

With Firefox 27, the site http://www.copperpages.com/ is rendered different to if it's addressed through http://copperpages.com/ . The difference is that through the URL with www. the images and some part of HTML code isn't rendered, while through the URL without www. all is rendered just like previous versions of Firefox. No issues with other browsers, Chrome/Safari/IE works same and fine with both versions of URL, with or without www prefix. Not sure about Firefox 26, maybe the issue was there, too.

What is the reason of the different page rendering with and without www prefix ?

With Firefox 27, the site http://www.copperpages.com/ is rendered different to if it's addressed through http://copperpages.com/ . The difference is that through the URL with www. the images and some part of HTML code isn't rendered, while through the URL without www. all is rendered just like previous versions of Firefox. No issues with other browsers, Chrome/Safari/IE works same and fine with both versions of URL, with or without www prefix. Not sure about Firefox 26, maybe the issue was there, too. What is the reason of the different page rendering with and without www prefix ?

Chosen solution

You can inspect and manage the permissions the domain of the currently selected tab via these steps:

  • Click the "Site Identity Button" (globe/padlock) on the location bar
  • Click "More Information" to open the "Page Info > Security" window
  • Go to the Permissions tab (Tools > Page Info > Permissions) to check the permissions the domain of the currently selected tab

You can remove all data stored in Firefox from a specific domain via "Forget About This Site" in the right-click context menu of an history entry ("History > Show All History" or "View > Sidebar > History") or via the about:permissions page.

Using "Forget About This Site" will remove all data stored in Firefox from that domain like bookmarks, cookies, passwords, cache, history, and exceptions, so be cautious and if you have a password or other data from that domain that you do not want to lose then make sure to backup this data or make a note.

You can't recover from this 'forget' unless you have a backup of the involved files.

It doesn't have any lasting effect, so if you revisit such a 'forgotten' website then data from that website will be saved once again.

Read this answer in context 👍 0

All Replies (6)

more options

No difference here between the two pages.

Reload web page(s) and bypass the cache to refresh possibly outdated or corrupted files.

  • Hold down the Shift key and left-click the Reload button
  • Press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
  • Press "Command + Shift + R" (Mac)

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

  • Do NOT click the Reset button on the Safe Mode start window.

You can also use the Inspector (Firefox/Tools > Web Developer;Ctrl+Shift+I) to check the Network log.

more options

Cor-el, thank you for your response. Unfortunately, I still can't figure the issue out. By points, 1. Reloading the pages has changed nothing, pages are still different. 2. Safe mode - the same result, nothing is changed. 3. In the Network Log I see: - 29 requests for http://copperpages.com/ (that's right) - 7 requests for http://www.copperpages.com/ (all the image files are missed) But I can't understand why Firefox didn't request for all the image files? Could you suppose some reason for that? Thanks for your reply.

Just am going to add, I didn't notice issues with other websites since the v.27 was installed a few days ago.

more options

Just to add to my previous post,

I've tried to address one of those image files through its URL with and without www and both are displayed correctly - when addressed separately as http://copperpages.com/img/logo2.gif and http://www.copperpages.com/img/logo2.gif

So, it seems like Firefox doesn't post requests for those images when the whole page is addressed with www: http://www.copperpages.com/

What could be the reason?

more options

Chosen Solution

You can inspect and manage the permissions the domain of the currently selected tab via these steps:

  • Click the "Site Identity Button" (globe/padlock) on the location bar
  • Click "More Information" to open the "Page Info > Security" window
  • Go to the Permissions tab (Tools > Page Info > Permissions) to check the permissions the domain of the currently selected tab

You can remove all data stored in Firefox from a specific domain via "Forget About This Site" in the right-click context menu of an history entry ("History > Show All History" or "View > Sidebar > History") or via the about:permissions page.

Using "Forget About This Site" will remove all data stored in Firefox from that domain like bookmarks, cookies, passwords, cache, history, and exceptions, so be cautious and if you have a password or other data from that domain that you do not want to lose then make sure to backup this data or make a note.

You can't recover from this 'forget' unless you have a backup of the involved files.

It doesn't have any lasting effect, so if you revisit such a 'forgotten' website then data from that website will be saved once again.

more options

Yes! I found the images are locked for the domain with www. Betting I didn't do this on purpose...

Thank you for your help Cor-el!

more options

You're welcome