However, as we approach 2025, with growing concerns about online privacy and data protection, Mozilla believes that DNT is no longer an effective privacy measure. Many websites ignore the DNT signal. Therefore, Mozilla has removed the DNT signal from Firefox version 135.
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Mozilla believes that privacy preference is not honored by websites and that sending the Do Not Track signal may impact your privacy. The company has updated Firefox’s Do Not Track help support page to confirm that.
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The company recommends using the Global Privacy Control setting as an alternative to prevent websites from tracking user data.
I think the article made a typo that claims GPC is the same as DNT.
When you enable the feature, the GPC sends a signal… This signal is sent via a special HTTP header called DNT: 1 (Do Not Track)
But the GPC spec does say it sends a new signal: Another header (like DNT) and a JavaScript variable the client would set. I don’t see why this couldn’t be used for tracking too.
A user agent MUST generate a Sec-GPC header
So if it generates a header, it can still be used for fingerprinting, but this header is actually less restrictive for what the receiver must do.
DNT was “do not track,” and GPC is "do not sell:
GPC is also not intended to limit a first party’s use of personal information within the first-party context (such as a publisher targeting ads to a user on its website based on that user’s previous activity on that same site).
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I think the article made a typo that claims GPC is the same as DNT.
But the GPC spec does say it sends a new signal: Another header (like DNT) and a JavaScript variable the client would set. I don’t see why this couldn’t be used for tracking too.
So if it generates a header, it can still be used for fingerprinting, but this header is actually less restrictive for what the receiver must do.
DNT was “do not track,” and GPC is "do not sell: