A pseudo-class for matching elements in a selector list. 

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@csstools/postcss-is-pseudo-class

A pseudo-class for matching elements in a selector list

jonathantneal

alaguna

romainmenke

postcss-is-pseudo-class

(Experimental) An ambiguous license classifier was found.

What is an ambiguous license classifier?

Ambiguous License Classifier

Source files are encoded using a non-standard text encoding.

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Bad text encoding

Package version is not a valid semantic version (semver).

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Bad semver

Package has dependencies with an invalid semantic version. This could be a sign of beta, low quality, or unmaintained dependencies.

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Bad dependency semver

Source files contain bidirectional unicode control characters. This could indicate a Trojan source supply chain attack. See: trojansource.codes for more information.

What are bidirectional unicode control characters?

Bidirectional unicode control characters

This package has multiple bin scripts with the same name. This can cause non-deterministic behavior when installing or could be a sign of a supply chain attack.

What is bin script confusion?

Bin script confusion

This Chrome extension includes a content script '{scriptFile}' that runs on websites matching '{matches}'.

What are Chrome extension content scripts?

Chrome Extension Content Script

This Chrome extension requests access to '{host}'.

What are Chrome extension host permissions?

Chrome Extension Host Permission

This Chrome extension uses the '{permission}' permission.

What are Chrome extension permissions?

Chrome Extension Permission

This Chrome extension requests broad access to websites with the pattern '{host}'.

What are Chrome extension wildcard host permissions?

Chrome Extension Wildcard Host Permission

Semantic versions published out of chronological order.

What is a chronological version anomaly?

Chronological version anomaly

Project maintainer's SSH key has been compromised.

What is a compromised SSH key?

Compromised SSH key

(Experimental) Copyleft license information was found.

What do I need to know about license files?

Copyleft License

Contains a Critical Common Vulnerability and Exposure (CVE).

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Title

Critical CVE

Contains a high severity Common Vulnerability and Exposure (CVE).

What is a CVE?

High CVE

Uses debug, reflection and dynamic code execution features.

What is debug access?

Debug access

The maintainer of the package marked it as deprecated. This could indicate that a single version should not be used, or that the package is no longer maintained and any new vulnerabilities will not be fixed.

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Deprecated

(Experimental) Contains a known deprecated SPDX license exception.

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Deprecated SPDX exception

(Experimental) License is deprecated which may have legal implications regarding the package's use.

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Deprecated license

Package name is similar to other popular packages and may not be the package you want.

What is a typosquat?

Possible typosquat attack

Dynamic require can indicate the package is performing dangerous or unsafe dynamic code execution.

What is dynamic require?

Dynamic require

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Empty package

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

What is environment variable access?

Environment variable access

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Explicitly Unlicensed Item

Package optionally loads a dependency which is not specified within any of the package.json dependency fields. It may inadvertently be importing dependencies specified by other packages.

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Name

Extraneous dependency

Contains a dependency which resolves to a file. This can obfuscate analysis and serves no useful purpose.

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File dependency

Accesses the file system, and could potentially read sensitive data.

What is filesystem access?

Filesystem access

Package has a dependency with a floating version range. This can cause issues if the dependency publishes a new major version.

What are wildcard dependencies?

Wildcard dependency

Contains a dependency which resolves to a remote git URL. Dependencies fetched from git URLs are not immutable and can be used to inject untrusted code or reduce the likelihood of a reproducible install.

What are git dependencies?

Git dependency

Contains a dependency which resolves to a GitHub URL. Dependencies fetched from GitHub specifiers are not immutable can be used to inject untrusted code or reduce the likelihood of a reproducible install.

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GitHub dependency

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What is an AI-detected potential code anomaly?

AI-detected potential code anomaly

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AI-detected possible typosquat

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AI-detected potential malware

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AI-detected potential security risk

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Native code

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High entropy strings

Contains unicode homoglyphs which can be used in supply chain confusion attacks.

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Unicode homoglyphs

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HTTP dependency

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Install scripts

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Invalid manifest file

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Invisible chars

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License exception

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License Policy Violation

Contains long string literals, which may be a sign of obfuscated or packed code.

What's wrong with long strings?

Long strings

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

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Major refactor

This package is identified as malware. It has been flagged either by Socket's AI scanner and confirmed by our threat research team, or is listed as malicious in security databases and other sources.

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Known malware

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What is manifest confusion?

Manifest confusion

Contains a medium severity Common Vulnerability and Exposure (CVE).

What is a medium CVE?

Medium CVE

Contains a low severity Common Vulnerability and Exposure (CVE).

What is a mild CVE?

Low CVE

This package contains minified code. This may be harmless in some cases where minified code is included in packaged libraries, however packages on npm should not minify code.

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Minified code

(Experimental) A package's licensing information has fine-grained problems.

Misc. License Issues

The package was published by an npm account that no longer exists.

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Non-existent author

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Missing dependency

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Missing license

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Missing package tarball

(Experimental) Package contains multiple licenses.

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Mixed license

(Experimental) Package contains a modified version of an SPDX license exception. Please read carefully before using this code.

What is a modified license exception?

Modified license exception

(Experimental) Package contains a modified version of an SPDX license. Please read carefully before using this code.

What is a modified license?

Modified license

What is network access?

Network access

A new npm collaborator published a version of the package for the first time. New collaborators are usually benign additions to a project, but do indicate a change to the security surface area of a package.

What is new author?

New author

Package does not specify a list of contributors or an author in package.json.

Why is contributor and author data important?

No contributors or author data

Package does not have a linked bug tracker in package.json.

Why are bug trackers important?

No bug tracker

(Experimental) License information could not be found.

No License Found

Package does not have a README. This may indicate a failed publish or a low quality package.

		# Changes to PostCSS Is Pseudo Class

		### 5.0.1
		### 5.0.2

		_October 23, 2024_
		_June 10, 2025_

		- Make sorting compound selectors forwards compatible with potential future changes in `postcss-selector-parser`
		- Updated: `postcss-selector-parser`
		- Updated [`@csstools/selector-specificity`](https://github.com/csstools/postcss-plugins/tree/main/packages/selector-specificity) to [`5.0.0`](https://github.com/csstools/postcss-plugins/tree/main/packages/selector-specificity/CHANGELOG.md#500) (major)
		- Add support for more complex selector patterns. `.a > :is(.b > .c)` -> `.a.b > .c`

		[Full CHANGELOG](https://github.com/csstools/postcss-plugins/tree/main/plugins/postcss-is-pseudo-class/CHANGELOG.md)

		{
		"name": "@csstools/postcss-is-pseudo-class",
		"description": "A pseudo-class for matching elements in a selector list",
		"version": "5.0.1",
		"version": "5.0.2",
		"author": "Jonathan Neal <jonathantneal@hotmail.com>",
		@@ -6,0 +6,0 @@ "license": "MIT-0",

		# PostCSS Is Pseudo [<img src="https://postcss.github.io/postcss/logo.svg" alt="PostCSS" width="90" height="90" align="right">][postcss]

		[![NPM Version][npm-img]][npm-url]
		[<img alt="Build Status" src="https://github.com/csstools/postcss-plugins/workflows/test/badge.svg" height="20">][cli-url]
		[<img alt="Build Status" src="https://github.com/csstools/postcss-plugins/actions/workflows/test.yml/badge.svg?branch=main" height="20">][cli-url]
		[<img alt="Discord" src="https://shields.io/badge/Discord-5865F2?logo=discord&logoColor=white">][discord]
		@@ -13,3 +13,3 @@ <br><br>

		```pcss
		```css
		:is(input, button):is(:hover, :focus) {
		@@ -22,3 +22,3 @@ order: 1;

		```pcss
		```css
		input:hover {
		@@ -75,3 +75,3 @@ order: 1;

		```pcss
		```css
		:is(input, button):is(:hover, :focus) {
		@@ -84,3 +84,3 @@ order: 1;

		```pcss
		```css
		input:hover {
		@@ -117,3 +117,3 @@ order: 1;

		```pcss
		```css
		:is(.button, button):hover {
		@@ -126,3 +126,3 @@ order: 7;

		```pcss
		```css
		.button:hover {
		@@ -185,3 +185,3 @@ order: 7;

		```pcss
		```css
		:is(:hover, :focus):is(.button, button) {
		@@ -194,3 +194,3 @@ order: 7;

		```pcss
		```css
		/* specificity: [0, 2, 0] */
		@@ -224,3 +224,3 @@ .button:hover {

		```pcss
		```css
		:is(.alpha > .beta) ~ :is(:focus > .beta) {
		@@ -233,3 +233,3 @@ order: 2;

		```pcss
		```css
		.alpha > .beta ~ :focus > .beta {
		@@ -244,3 +244,3 @@ order: 2;

		```pcss
		```css
		/* without is */
		@@ -247,0 +247,0 @@ .alpha:focus > .beta ~ .beta {

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