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nytimes detecting Private Mode

  • 4 replies
  • 2 have this problem
  • 3 views
  • Last reply by Jeenu

Jeenu
Jeenu
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I updated to Firefox 66 on Linux yesterday. I don't know if it's the browser version, but I noticed that nytimes.com started picking up that I'm browsing the site in private mode.

Interestingly, this is something that used to happen on my Chrome book when I used private mode, but this on Firefox, this is a first for me. It may well be that nytimes changed their code to do this, but I wonder upgrade to FF 66 contributed to this.

In any case, I wonder how a site can pick up if the user is browsing in private mode.

I updated to Firefox 66 on Linux yesterday. I don't know if it's the browser version, but I noticed that nytimes.com started picking up that I'm browsing the site in private mode. Interestingly, this is something that used to happen on my Chrome book when I used private mode, but this on Firefox, this is a first for me. It may well be that nytimes changed their code to do this, but I wonder upgrade to FF 66 contributed to this. In any case, I wonder how a site can pick up if the user is browsing in private mode.

All Replies (4)

WestEnd
WestEnd
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PB if detected by the site might now let you access since they sometimes require tracking or cookies to work.

Modified by WestEnd

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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In private windows, Firefox disables saving data to disk using IndexedDB, so that is one possible characteristic sites might use.

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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There was a thread on Reddit recently:

https://www.reddit.com/r/firefox/comments/b0c5ea/preventing_incognito_mode_detection/

Jeenu
Jeenu Question owner
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Thanks.

A 7-years-old bug!