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What can lead to a CRSF authentication error (FF only) that is related to the FF profile?

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  • Last reply by cor-el
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mr.user1
mr.user1

The hint here 

 https://support.mozilla.org/en-US/questions/1207335

is to create a blank profile if I get access denied for a CRSF (FF only). This hint worked for me, while it still keeps me puzzled. In the original profile even if I disabled all the addons, I could still reproduce the CRSF issue. There are also extensions though. I could not identify the external site using the dev tools / network. At least it showed me just a single url source.

Question: Is there blacklist of addons/extensions/plugins doing CRSF? Do you have any suggestion how I could spot the reason? Is there a way to step by step building up the profile e.g. with sqlite while keeping it consistent?

FF 65.02 x64 win

The hint here https://support.mozilla.org/en-US/questions/1207335 is to create a blank profile if I get access denied for a CRSF (FF only). This hint worked for me, while it still keeps me puzzled. In the original profile even if I disabled all the addons, I could still reproduce the CRSF issue. There are also extensions though. I could not identify the external site using the dev tools / network. At least it showed me just a single url source. Question: Is there blacklist of addons/extensions/plugins doing CRSF? Do you have any suggestion how I could spot the reason? Is there a way to step by step building up the profile e.g. with sqlite while keeping it consistent? FF 65.02 x64 win

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cor-el
cor-el
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A CSRF (Cross-Site Request Forgery) token is used by websites to make sure that there isn't tampered with this request (i.e. the request isn't coming from another server/website).

You can see these tokens in the page source of this page (right-click -> "View Page Source") as hidden input fields. If these tokens are missing or corrupted then the server knows something is wrong.

If this isn't a problem with Firefox then maybe your security software is causing this issue.

You can create a new profile to test if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block (wanted) content (Adblock Plus, NoScript, Disconnect, Ghostery, Privacy Badger, uBlock Origin) always make sure such extensions do not block (wanted) content.

You can try these steps in case of issues with web pages:

You can 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)

Clear the Cache and remove the Cookies from websites that cause problems via the "3-bar" Firefox menu button (Options/Preferences).

"Remove the Cookies" from websites that cause problems:

  • Options/Preferences -> Privacy & Security
    Cookies and Site Data -> Manage Data

"Clear the Cache":

  • Options/Preferences -> Privacy & Security
    Cookies and Site Data -> Clear Data -> Cached Web Content: Clear

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window