diff --git a/src/vs/base/common/strings.ts b/src/vs/base/common/strings.ts
index 3931adefd65..02d9179c792 100644
--- a/src/vs/base/common/strings.ts
+++ b/src/vs/base/common/strings.ts
@@ -217,10 +217,6 @@ export function regExpLeadsToEndlessLoop(regexp: RegExp): boolean {
 	return !!(match && regexp.lastIndex === 0);
 }
 
-export function regExpContainsBackreference(regexpValue: string): boolean {
-	return !!regexpValue.match(/([^\\]|^)(\\\\)*\\\d+/);
-}
-
 export function splitLines(str: string): string[] {
 	return str.split(/\r\n|\r|\n/);
 }
diff --git a/src/vs/base/test/common/strings.test.ts b/src/vs/base/test/common/strings.test.ts
index f4bea3785b8..18e53a2e5d0 100644
--- a/src/vs/base/test/common/strings.test.ts
+++ b/src/vs/base/test/common/strings.test.ts
@@ -265,22 +265,6 @@ suite('Strings', () => {
 		assert(regExpWithFlags.multiline);
 	});
 
-	test('regExpContainsBackreference', () => {
-		assert(strings.regExpContainsBackreference('foo \\5 bar'));
-		assert(strings.regExpContainsBackreference('\\2'));
-		assert(strings.regExpContainsBackreference('(\\d)(\\n)(\\1)'));
-		assert(strings.regExpContainsBackreference('(A).*?\\1'));
-		assert(strings.regExpContainsBackreference('\\\\\\1'));
-		assert(strings.regExpContainsBackreference('foo \\\\\\1'));
-
-		assert(!strings.regExpContainsBackreference(''));
-		assert(!strings.regExpContainsBackreference('\\\\1'));
-		assert(!strings.regExpContainsBackreference('foo \\\\1'));
-		assert(!strings.regExpContainsBackreference('(A).*?\\\\1'));
-		assert(!strings.regExpContainsBackreference('foo \\d1 bar'));
-		assert(!strings.regExpContainsBackreference('123'));
-	});
-
 	test('getLeadingWhitespace', () => {
 		assert.strictEqual(strings.getLeadingWhitespace('  foo'), '  ');
 		assert.strictEqual(strings.getLeadingWhitespace('  foo', 2), '');