Resolve #5420 (#5421)

src/client/app/admin/views/federation.vue

@@ -509,7 +509,7 @@ export default Vue.extend({
 
 		saveBlockedHosts() {
 			this.$root.api('admin/update-meta', {
-				blockedHosts: this.blockedHosts.split('\n')
+				blockedHosts: this.blockedHosts ? this.blockedHosts.split('\n') : []
 			}).then(() => {
 				this.$root.dialog({
 					type: 'success',

src/client/app/admin/views/instance.vue

@@ -461,7 +461,7 @@ export default Vue.extend({
 				iconUrl: this.iconUrl,
 				name: this.name,
 				description: this.description,
-				langs: this.languages.split(' '),
+				langs: this.languages ? this.languages.split(' ') : [],
 				cacheRemoteFiles: this.cacheRemoteFiles,
 				localDriveCapacityMb: parseInt(this.localDriveCapacityMb, 10),
 				remoteDriveCapacityMb: parseInt(this.remoteDriveCapacityMb, 10),
@@ -490,8 +490,8 @@ export default Vue.extend({
 				enableServiceWorker: this.enableServiceWorker,
 				swPublicKey: this.swPublicKey,
 				swPrivateKey: this.swPrivateKey,
-				pinnedUsers: this.pinnedUsers.split('\n'),
-				hiddenTags: this.hiddenTags.split('\n'),
+				pinnedUsers: this.pinnedUsers ? this.pinnedUsers.split('\n') : [],
+				hiddenTags: this.hiddenTags ? this.hiddenTags.split('\n') : [],
 				useObjectStorage: this.useObjectStorage,
 				objectStorageBaseUrl: this.objectStorageBaseUrl ? this.objectStorageBaseUrl : null,
 				objectStorageBucket: this.objectStorageBucket ? this.objectStorageBucket : null,