From e4ca324d605370a83d29e8be6706059527922698 Mon Sep 17 00:00:00 2001
From: Matt Wang <matt@matthewwang.me>
Date: Sat, 16 May 2020 00:53:54 -0700
Subject: [PATCH] ignores WebExtension replacement keywords in
 isStandardSyntaxValue

+ two basic tests
---
 lib/utils/__tests__/isStandardSyntaxValue.test.js | 6 ++++++
 lib/utils/isStandardSyntaxValue.js                | 7 +++++++
 2 files changed, 13 insertions(+)

diff --git a/lib/utils/__tests__/isStandardSyntaxValue.test.js b/lib/utils/__tests__/isStandardSyntaxValue.test.js
index 44031c13ac..f5a66559a2 100644
--- a/lib/utils/__tests__/isStandardSyntaxValue.test.js
+++ b/lib/utils/__tests__/isStandardSyntaxValue.test.js
@@ -42,4 +42,10 @@ describe('isStandardSyntaxValue', () => {
 	it('less interpolation', () => {
 		expect(isStandardSyntaxValue('@{var}')).toBeFalsy();
 	});
+	it('WebExtension replacement keyword', () => {
+		expect(isStandardSyntaxValue('__MSG_@@bidi_dir__')).toBeFalsy();
+	});
+	it('negative WebExtension replacement keyword', () => {
+		expect(isStandardSyntaxValue('__msg_@@bidi_dir__')).toBeTruthy();
+	});
 });
diff --git a/lib/utils/isStandardSyntaxValue.js b/lib/utils/isStandardSyntaxValue.js
index f7da6ef853..5f8b430301 100644
--- a/lib/utils/isStandardSyntaxValue.js
+++ b/lib/utils/isStandardSyntaxValue.js
@@ -36,5 +36,12 @@ module.exports = function (value) {
 		return false;
 	}
 
+	// WebExtension replacement keyword used by Chrome/Firefox
+	// more information: https://developer.chrome.com/extensions/i18n
+	// and https://github.com/stylelint/stylelint/issues/4707
+	if (/__MSG_[^\s]+__/.test(value)) {
+		return false;
+	}
+
 	return true;
 };