Filter syntax extensions

µBlock supports most of Adblock Plus filter syntax. However µBlock does not support some very specific case, and also added its own extensions to ABP filter syntax.

Not supported

document:

Not supported. The purpose of the document option is to disable µBlock completely. The reason it is not supported is to be sure that users explicitly disable µBlock themselves if they wish (through whitelisting), not having some external filter list decide for them.

Extended syntax

µBlock extends Adblock Plus filter syntax.

Network filters

important:

The filter option important means to ignore all exception filters (those prefixed with @@).

It applies only to net block filters. The important option will allow you to block with 100% certainty specific net requests.

Example: ||google-analytics.com^$important,third-party will block all net requests to google-analytics.com, disregarding any existing network exception filters. Another example: ||twitter.com^$important,third-party. Etc.

inline-script:

To specifically disable inline script tags in a main page: ||example.com^$inline-script.

Cosmetic filters

Entity-based cosmetic filters: Filters which are to be applied to a specific entity.

An entity is defined as follow: a formal domain name with the Public Suffix part replaced by a wildcard.

Examples: google.* will apply to all similar Google domain names: google.com, google.com.br, google.ca, google.co.uk, etc. Another example: facebook.* will apply to all similar Facebook domain names: facebook.com, facebook.net.