Feature/improve validation of currency management (#2761)

* Improve validation

* Update changelog

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 
 - Set the select column of the lazy-loaded activities table to stick at the end (experimental)
+- Improved the validation of the currency management in the admin control panel
 - Improved the performance of the value redaction interceptor for the impersonation mode by eliminating `cloneDeep`
 
 ### Fixed

apps/client/src/app/components/admin-overview/admin-overview.component.ts

@@ -119,8 +119,12 @@ export class AdminOverviewComponent implements OnDestroy, OnInit {
     const currency = prompt($localize`Please add a currency:`);
 
     if (currency) {
-      const currencies = uniq([...this.customCurrencies, currency]);
-      this.putAdminSetting({ key: PROPERTY_CURRENCIES, value: currencies });
+      if (currency.length === 3) {
+        const currencies = uniq([...this.customCurrencies, currency]);
+        this.putAdminSetting({ key: PROPERTY_CURRENCIES, value: currencies });
+      } else {
+        alert($localize`${currency} is an invalid currency!`);
+      }
     }
   }