Use regex to check for email on RegisterPage

src/components/RegisterPage.vue

@@ -33,6 +33,8 @@
 </template>
 
 <script>
+import { isEmail } from "../utils/Misc.js";
+
 export default {
     data() {
         return {
@@ -52,7 +54,7 @@ export default {
     methods: {
         register() {
             if (!this.username || !this.password) return;
-            if (this.username.includes("@") && !confirm(this.$t("info.register_no_email_note"))) return;
+            if (isEmail(this.username) && !confirm(this.$t("info.register_no_email_note"))) return;
 
             this.fetchJson(this.authApiUrl() + "/register", null, {
                 method: "POST",

src/utils/Misc.js

@@ -0,0 +1,8 @@
+export const isEmail = input => {
+    // Taken from https://emailregex.com
+    const result = input.match(
+        //eslint-disable-next-line
+        /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/,
+    );
+    return result;
+};