diff --git a/packages/backend/src/misc/normalize-email-address.ts b/packages/backend/src/misc/normalize-email-address.ts
index eab876d170fc..126eefa7e4cf 100644
--- a/packages/backend/src/misc/normalize-email-address.ts
+++ b/packages/backend/src/misc/normalize-email-address.ts
@@ -1,4 +1,4 @@
-const specialCharactersRegexp = /(\(.*?\)|(\+.*(?=@)))/u;
+const specialCharactersRegexp = /(\(.*?\)|(\+.*(?=@)))/gu;
 
 export function normalizeEmailAddress(email: string | null): string | null {
 	return email?.replaceAll(specialCharactersRegexp, '') ?? null;