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firefox keeps blocking 3rd party cookies their settings do not work

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A website I use to move money - getting message telling me cookies is blocking 3rd party cookies. and I need to enable 3rd party cookies. I go to settings in firefox and for the information to set settings to enable cookies 3rd party they do not work. They tell me to check and uncheck boxes that I do not even have for setttings. I never had this problem before until Jan. of 2022. I have to use a different browser to get to the website and complete my task. There is something in the Firefox browser or they made changes/updates. Need step by step instructions. NEED TO TALK TO SOMEONE.

A website I use to move money - getting message telling me cookies is blocking 3rd party cookies. and I need to enable 3rd party cookies. I go to settings in firefox and for the information to set settings to enable cookies 3rd party they do not work. They tell me to check and uncheck boxes that I do not even have for setttings. I never had this problem before until Jan. of 2022. I have to use a different browser to get to the website and complete my task. There is something in the Firefox browser or they made changes/updates. Need step by step instructions. NEED TO TALK TO SOMEONE.

Chosen solution

Here's a brief update:

Firefox 96 made three changes related to cookies that affect when they will be served to third party servers.

(1) If the server does not specify the SameSite setting for its cookies, Firefox changed from treating it as SameSite=None (allow serving as a third party cookie) to SameSite=Lax (partially restricts serving as a third party cookie).

Users have reported two different servers with this issue so far:

  1. iCloud: https://support.mozilla.org/questions/1364242
  2. Canvas/Kaltura

To diagnose this issue, you can experiment with a setting, which is noted later in this post, below the line.

(2) If the cookie was set on an HTTPS page, it is not automatically passed to HTTP pages on the same server. In other words, SameSite consider the protocol (scheme) as well as the host name. This is a problem for older sites that use HTTP for most pages but do the login over HTTPS. Example: https://www.reddit.com/r/firefox/comments/s3iych/south_korea_cant_sign_in_to_some_websites_after/

A hotfix was released Friday to revert change #2 back to the Firefox 95 behavior.

(3) If the server specifies that third party cookies are okay by setting SameSite=None, this is only honored for HTTPS pages, not HTTP pages. I don't know whether this is causing problems on any sites.


How to test whether this is issue #1:

(A) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.

(B) In the search box in the page, type or paste laxByDefault and pause while the list is filtered

(C) Double-click the network.cookie.sameSite.laxByDefault preference to switch the value from true to false

I don't know whether that takes effect immediately or whether you need to quit Firefox and start it up again.

Hopefully we will get a better understanding of how to set exceptions in the future so you can benefit from this change while using other sites.

Read this answer in context 👍 0

All Replies (16)

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https://support.mozilla.org/en-US/kb/websites-say-cookies-are-blocked-unblock-them


Make sure you are not blocking content.

https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop also see https://blog.mozilla.org/security/2021/03/23/introducing-smartblock/

https://support.mozilla.org/en-US/kb/smartblock-enhanced-tracking-protection


Diagnose Firefox issues using Troubleshoot(Safe) Mode {web link}

A small dialog should appear. Click Start In Troubleshoot(Safe) Mode (not Refresh). Is the problem still there?


Many site issues can be caused by corrupt cookies or cache.

Warning ! ! This will log you out of sites you're logged in to. You may also lose any settings for that website.

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Firefox 96 made some technical changes to how cookies work. This link is for the support team at the site, if you could mention it to them:

https://developer.mozilla.org/en-US/docs/Mozilla/Firefox/Releases/96#http

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Does not tell me a thing how to fix.

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marschall3 said

Does not tell me a thing how to fix.

If you meant my post, yes, that is for the site to check whether their design works with Firefox 96.

Meanwhile, did you try deleting the old cookies for the problem sites?

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Hello jscher 2000 Thank you for trying to help me with your post. I am not a computer wiz. Not sure what that means to me. There's a lot going on there with the reading. The problem is with firefox browser. I tried all there recommendations for there settings on firefox. None of there settings match my settings. Here's what is happening.. I go to my bank website to move money with( popmoney. ) I keep getting a message telling me my browser is blocking 3rd party cookies. and go the browser settings and enable 3rd party cookies settings. Well there is no check boxes to do this on their settings to do this. Firefox shows what to do but they settings that they show me does not match my settings on Firefox settings. Never had this issue until Jan. 1 ,2022. Firefox had to have changed something. ( I did do updates with Firefox.) I called Geek Squad and the only way I could complete my task with my bank is to use a different web browser. Google Chrome. Than it works. I will keep doing my home work to try and solve my problem. Thank You

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yes I did delete old cookies

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Yesterday's update modified cookies in a way I don't fully understand. However, it appears that sites must now mark their cookies as being able to be used as third party cookies. That is why the link to the developer site is meant for your bank and not for you.

As I learn more about this I'll come back and update this thread.

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Thanks that will be great! In the mean time I will go back and look at your post and try to see if I can figure it out.

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I am glad Firefox is aware of the problem and I have notified both of my credit unions about it. One CU suggested that I use Chrome. I won't be doing that.

Modified by John Stewart

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Chosen Solution

Here's a brief update:

Firefox 96 made three changes related to cookies that affect when they will be served to third party servers.

(1) If the server does not specify the SameSite setting for its cookies, Firefox changed from treating it as SameSite=None (allow serving as a third party cookie) to SameSite=Lax (partially restricts serving as a third party cookie).

Users have reported two different servers with this issue so far:

  1. iCloud: https://support.mozilla.org/questions/1364242
  2. Canvas/Kaltura

To diagnose this issue, you can experiment with a setting, which is noted later in this post, below the line.

(2) If the cookie was set on an HTTPS page, it is not automatically passed to HTTP pages on the same server. In other words, SameSite consider the protocol (scheme) as well as the host name. This is a problem for older sites that use HTTP for most pages but do the login over HTTPS. Example: https://www.reddit.com/r/firefox/comments/s3iych/south_korea_cant_sign_in_to_some_websites_after/

A hotfix was released Friday to revert change #2 back to the Firefox 95 behavior.

(3) If the server specifies that third party cookies are okay by setting SameSite=None, this is only honored for HTTPS pages, not HTTP pages. I don't know whether this is causing problems on any sites.


How to test whether this is issue #1:

(A) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.

(B) In the search box in the page, type or paste laxByDefault and pause while the list is filtered

(C) Double-click the network.cookie.sameSite.laxByDefault preference to switch the value from true to false

I don't know whether that takes effect immediately or whether you need to quit Firefox and start it up again.

Hopefully we will get a better understanding of how to set exceptions in the future so you can benefit from this change while using other sites.

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Hello Thank you for the update! I will check it out. I will have to let you know in the next couple of days to see what happens. I will keep in touch. (going to be away a few days) Thanks Again!! marschall3

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Hi jscher 2000 Good news. I tried your method for how to test with issue #1. It seemed to work !!!! Took affect immediately. I will test it a few more times to see if it holds true. If it does I want to thank you for your GREAT effort on helping me. Much appreciated! One more problem solved thanks to you. Would have never figured that out on my own. Give it a day or two and I will let you know. Thank You Very Much Marschall3

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TO jscher2000 Problem Solved. Your solution for issue #1 worked. I followed the steps that you gave me in the about:config method. Worked right away - no problem! Thanks for helping me solving my problem with Firefox browser!!! Have a great day!!! marschall3

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Thank you for reporting back. If you have time, could you let the site know about this problem? You can give them a link to this thread: https://support.mozilla.org/questions/1364032

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I just tried going into about:config and network.cookie.sameSite.laxByDefault was already false. Trying to set true and that didn't help.

My primary site to test is walmart.com.

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mike-a said

I just tried going into about:config and network.cookie.sameSite.laxByDefault was already false. Trying to set true and that didn't help. My primary site to test is walmart.com.

As far as I can tell, you do not need to change the default setting to log in to the Walmart site. Where do you get the message about third party cookies? If you aren't getting that message, let's continue the discussion in your other thread.