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How to hide default screen size in Firefox?

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  • Last reply by cor-el

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How can i hide my display/screen resolution from websites? I use Firefox in windowed mode not with my default screen size but websites know my default resolution. This can be used to identify my pc. I dont want that for privacy reasons like tracking and adverstising. How can i prevent this? I found many threads/posts about this in various forums/websites. They are talking about Tor Browser and that websites can identify you if using full-screen mode. But as i said, im using Firefox not Tor and while im using windowed-mode websites still know my default resoltion. I tested this on https://whoer.net/

Another question, how can i restore the default window size in Firefox?

How can i hide my display/screen resolution from websites? I use Firefox in windowed mode not with my default screen size but websites know my default resolution. This can be used to identify my pc. I dont want that for privacy reasons like tracking and adverstising. How can i prevent this? I found many threads/posts about this in various forums/websites. They are talking about Tor Browser and that websites can identify you if using full-screen mode. But as i said, im using Firefox not Tor and while im using windowed-mode websites still know my default resoltion. I tested this on https://whoer.net/ Another question, how can i restore the default window size in Firefox?
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Chosen solution

Enabling sending DNT means that Firefox adds a DNT=1 header to the HTTP request headers, so you end up in a group that has this feature enabled, not a lot of browsers support this and it is not likely that a website support and honor this request. You can see this in the Network Monitor.

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Chosen Solution

Enabling sending DNT means that Firefox adds a DNT=1 header to the HTTP request headers, so you end up in a group that has this feature enabled, not a lot of browsers support this and it is not likely that a website support and honor this request. You can see this in the Network Monitor.

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-wrong thread

Modified by Firefox_Beginner

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Yeah, i know it's that extension, was woondering if it is true that using duckduckgo search without the extension is a security / privacy risk, like i said an article i read claimed duckduckgo search must be used in combination with the duckduckgo extension otherwise do not track wont work, but is that true or wrong? And anyways i have set to not track in firefox to always, why wont it work then?

Modified by Firefox_Beginner

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See also these prefs on the about:config page.

  • privacy.window.maxInnerWidth = 1000
  • privacy.window.maxInnerHeight = 1000
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