What Is Anti-Adblock and How Adless Bypasses It

You've seen the message: "We've detected you're using an ad blocker. Please disable it to continue reading." These anti-adblock walls are becoming increasingly common, with major publishers and platforms deploying sophisticated detection scripts to identify and block ad-blocker users.

How detection works

Anti-adblock detection typically uses one or more of these techniques:

Bait elements

The page creates a hidden element with class names like ad-banner or adsbox. If an ad blocker hides it (because the class name matches a cosmetic filter), the detection script checks its computed style and knows a blocker is active.

Script loading checks

The page attempts to load a script from a URL that looks like an ad (e.g., /ads/tracking.js). If the script fails to load or returns an error, the site knows it was blocked.

API fingerprinting

Some detection scripts check for the presence of extension-specific APIs or timing anomalies in chrome.runtime calls that indicate an extension is modifying page behavior.

How Adless stays invisible

Adless's camouflage engine addresses each detection vector:

1. Property shielding

The camouflage content script runs in the page's MAIN world and wraps extension-detectable properties with Proxy objects that return expected "no extension present" values. This defeats API fingerprinting.

2. Detector neutralization

Known detection script patterns are intercepted before they execute. The camouflage engine maintains a database of detection signatures (updated via Watchtower) and patches them to always report "no ad blocker detected."

3. Noop surrogates

Instead of blocking ad scripts (which would trigger loading-check detection), Adless redirects them to lightweight surrogate scripts that export the expected API surface but serve no ads. The page's detection logic sees a successfully loaded "ad script" and concludes no blocker is present.

4. Network-level invisibility

Because Adless uses declarativeNetRequest redirect rules (not block rules), from the page's perspective, ad requests succeed — they just return empty/noop content. No network errors, no failed fetches, no detectable blocking.

The arms race continues

Anti-adblock detection is an ongoing cat-and-mouse game, and Adless fights it on two fronts. For sites the camouflage engine already covers, its Watchtower server monitors for evolving detection signatures and streams updated signature data down in the background — no extension update or user action needed. But extending camouflage to a brand-new host is a different story: the list of sites where the MAIN-world camouflage script runs is baked into the extension's manifest, so bringing a new domain under that shield ships in a fresh, Chrome-reviewed release. We move fast, but that part always goes through the front door.

The fundamental advantage of Adless's approach is that it operates at the same privilege level as the detection scripts (MAIN world), uses the browser's own APIs for blocking (declarativeNetRequest), and serves convincing fake responses rather than simply blocking. It's not hiding — it's blending in.