👽 add missing translation support

src/app/app.module.ts

@@ -27,9 +27,21 @@ import {VotingChoiceComponent} from './pages/voting-choice/voting-choice.compone
 import {PasswordComponent} from './pages/password/password.component';
 import {HomeComponent} from './pages/home/home.component';
 import {HttpClient, HttpClientModule} from '@angular/common/http';
-import {TranslateLoader, TranslateModule, TranslateService} from '@ngx-translate/core';
+import {
+    MissingTranslationHandler,
+    MissingTranslationHandlerParams,
+    TranslateLoader,
+    TranslateModule,
+    TranslateService
+} from '@ngx-translate/core';
 import {TranslateHttpLoader} from '@ngx-translate/http-loader';
 
+export class MyMissingTranslationHandler implements MissingTranslationHandler {
+    handle(params: MissingTranslationHandlerParams) {
+        return 'some value';
+    }
+}
+
 registerLocaleData(localeFr, 'fr');
 
 export function HttpLoaderFactory(http: HttpClient) {
@@ -64,6 +76,11 @@ export function HttpLoaderFactory(http: HttpClient) {
         BrowserModule,
         AppRoutingModule,
         TranslateModule.forRoot({
+            missingTranslationHandler: {
+                provide: MissingTranslationHandler,
+                useClass: MyMissingTranslationHandler,
+            },
+            useDefaultLang: false,
             loader: {
                 provide: TranslateLoader,
                 useFactory: HttpLoaderFactory,