EFF, AdBlock and Others Launch New Do Not Track Standard
After years of discussions, disagreements, and digressions, the Do Not Track header is supported by all of the major browsers. But because there's no real requirement for sites or advertisers to respect it, DNT is not as effective as it could be.
Context & Ripple Effects
By mid-2015 the Do Not Track header had been supported by every major browser for years, yet the Microsoft decision to stop enabling it by default — reversing Internet Explorer 10's policy — showed how little the signal carried commercially. The W3C compounded that with an "intention to interact" carve-out letting companies like Facebook keep tracking logged-in users, effectively gutting the standard from the standards side.
This launch is the civil-society counterattack: rather than waiting for sites to volunteer compliance, EFF, AdBlock and their allies are trying to give the signal teeth through tooling — the same AdBlock whose later Edge availability and activist campaigns made it one of the web's largest distribution channels for privacy defaults. The arc closes nine years later when Mozilla removes DNT entirely in Firefox version 135, citing how few sites ever honored it.
First-order effects
- Sites and ad networks now receive the DNT signal alongside users who also run AdBlock, meaning ignoring the preference no longer costs nothing — the same client that sends the signal can block the tracker.
Second-order effects
- Advertisers face a forced choice between honoring the header and risking placement on blocklists maintained by the very tools distributing it, while browsers like Microsoft that dropped the default are sidelined as enforcers.
Third-order effects
- A voluntary, unenforceable header was always going to fail — Mozilla's 2024 removal confirms it — and privacy signaling migrates instead to legally backed opt-outs like Global Privacy Control, which lets a single click bind third-party data brokers.
The trend: Web privacy preferences are shifting from voluntary browser headers that sites may ignore toward enforced opt-out signals backed by blocking software and privacy law.