Fix fallback languages not loading (#631)

common/webapp/src/i18n.js

@@ -14,20 +14,24 @@ export const i18nModule = createI18n({
 export const i18n = i18nModule.global;
 
 export async function setLanguage(lang) {
+	loadLanguage(lang);
+
+	i18n.locale.value = lang;
+
+	document.querySelector('html').setAttribute('lang', lang);
+
+	return nextTick();
+}
+
+async function loadLanguage(lang) {
 	try {
-		if (!i18n.availableLocales.includes(lang)){
+		if (!i18n.availableLocales.includes(lang)) {
 			let messages = await fetchHocon(`./lang/${lang}.conf`);
 			i18n.setLocaleMessage(lang, messages);
 		}
-
-		i18n.locale.value = lang;
-
-		document.querySelector('html').setAttribute('lang', lang);
 	} catch (e) {
 		console.error(`Failed to load language '${lang}'!`, e);
 	}
-
-	return nextTick();
 }
 
 export async function loadLanguageSettings() {
@@ -37,20 +41,24 @@ export async function loadLanguageSettings() {
 	if (settings.useBrowserLanguage) {
 		const availableLanguages = settings.languages.map(lang => lang.locale);
 
-        for (let browserLanguage of navigator.languages) {
-            selectedLanguage = availableLanguages.find(lang => lang === browserLanguage);
-            if (selectedLanguage) break;
+		for (let browserLanguage of navigator.languages) {
+			selectedLanguage = availableLanguages.find(lang => lang === browserLanguage);
+			if (selectedLanguage) break;
 
-            let baseBrowserLanguage = browserLanguage.split('-')[0];
-            selectedLanguage = availableLanguages.find(lang => lang.startsWith(baseBrowserLanguage));
-            if (selectedLanguage) break;
-        }
+			let baseBrowserLanguage = browserLanguage.split('-')[0];
+			selectedLanguage = availableLanguages.find(lang => lang.startsWith(baseBrowserLanguage));
+			if (selectedLanguage) break;
+		}
 	}
 
 	if (!selectedLanguage) {
 		selectedLanguage = settings.default;
 	}
 
+	await loadLanguage('en');
+	await loadLanguage(settings.default);
+	i18nModule.global.fallbackLocale = [settings.default, 'en'];
+
 	i18n.languages = settings.languages;
 	await setLanguage(selectedLanguage);
 }