Specify a whitelist of allowed pseudo-element selectors.

  a::before {}
/**  ↑
 * This pseudo-element selector */

This rule ignores:

  • CSS2 pseudo-elements i.e. those prefixed with a single colon
  • selectors that use variable interpolation e.g. ::#{$variable} {}


array|string|regex: ["array", "of", "unprefixed", "pseudo-elements" or "regex"]|"pseudo-element"|/regex/


["before", "/^my-/i"]

The following patterns are considered violations:

a::after {}
a::not-my-pseudo-element {}

The following patterns are not considered violations:

a::before {}
a::my-pseudo-element {}
a::MY-OTHER-pseudo-element {}