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My DESKTOP Firefox act like mobile

My Firefox using on desktop computer act like mobile. It is seen on the Facebook. Suddenly FB change view to https://m.face.... and is changing again each time when I type https://face... or anything else. Also whole layout looks like on mobile (very weird and impossible for operating).

More - after this happening, I had communicate that I am using "NEW Web browser" and I have to login.

This is happening also on other pages which have both version - for desktop and mobile

My Firefox using on desktop computer act like mobile. It is seen on the Facebook. Suddenly FB change view to https://m.face.... and is changing again each time when I type https://face... or anything else. Also whole layout looks like on mobile (very weird and impossible for operating). More - after this happening, I had communicate that I am using "NEW Web browser" and I have to login. This is happening also on other pages which have both version - for desktop and mobile

All Replies (3)

Hi okiem, these issues might be related, it's hard to say.

(1) Facebook desktop vs. mobile site

As you know, Facebook changed its layout recently. The responsive layout should work with all different screen resolutions. If you try the full address https://www.facebook.com/ do you get redirected back to mobile or can you use the new layout?

(2) Facebook forgetting your previous authentication

Firefox recently got enabled to purge "first party" tracking cookies from various sites, including popular sites like Facebook and YouTube. This occurs approximately every 24 hours. The purge should not occur if you have visited the site in the past 30-45 days, but there is a problem if your Firefox is set to clear history: when you clear history, Firefox thinks you haven't visited the site recently at all.

To test whether this feature is causing the problem, here is how you turn it off:

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

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

(C) Double-click the privacy.purge_trackers.enabled preference to switch the value from true to false

Please let us know whether that makes any difference for you.

You can remove all data stored in Firefox for 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").

Using "Forget About This Site" will remove all data stored in Firefox for this domain like history and cookies and passwords and exceptions and cache, so be cautious. If you have a password or other data for 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 involved files.

If you revisit a 'forgotten' website then data for that website will be saved once again.

For Facebook, someone mentioned this as a possible side effect of the FB Purity extension in another thread.