September 1, 2022
AdGuard, a developer of ad blocking software, has unveiled a new ad blocking extension that meets Google’s Manifest 3 requirements.
According to the provider offering the new AdGuard extension, the tool is technically weaker than its predecessor mainly due to compliance with the new Google protocol.
An extension manifest outlines a developer’s permissions and capabilities in an extension for the Chrome browser. In version 3 of the manifest, Google changed the webRequest API to prevent extensions from altering data before it is displayed to users, rendering ad blockers useless.
One of these limitation protocols include abiding by a limit of 30,000 filtering rules and 5,000 dynamic rules set by users. Therefore, when a user installs multiple ad blocking extensions in his browser, a global limit of 330,000 filtering rules is applied, which limits the capabilities of AdGuard.
Another problem is the inability to load rules into the filtering engine from the extension’s server. With the new rules, AdGuard is now expected to define a set of declarative rules and let Chrome be in charge of the network filtering process. Since the new syntax for the rules is very limited, not all existing rules can be converted, including cookie rules that block certain trackers.
There is also the inability to update the rules directly from the server, which can delay updates and how AdGuard responds to new blocking requirements from website changes.
Other problems that ad blockers face in Manifest V3 are the fact that users can no longer view the filtering logs because the browser blocks the ads, and the decision to replace the background page with a service worker thereby limiting performance.
The sources for this piece include an article in BleepingComputer.
