diff --git a/dev/App/User.js b/dev/App/User.js
index 0736a979e..cb04fa0e0 100644
--- a/dev/App/User.js
+++ b/dev/App/User.js
@@ -176,10 +176,6 @@ class AppUser extends AbstractApp {
 		);
 	}
 
-	recacheInboxMessageList() {
-		Remote.messageList(null, {Folder: getFolderInboxName()}, true);
-	}
-
 	messagesMoveTrigger() {
 		const sTrashFolder = FolderUserStore.trashFolder(),
 			sSpamFolder = FolderUserStore.spamFolder();
@@ -515,7 +511,7 @@ class AppUser extends AbstractApp {
 								if (folderFromCache.fullNameRaw === FolderUserStore.currentFolderFullNameRaw()) {
 									this.reloadMessageList();
 								} else if (getFolderInboxName() === folderFromCache.fullNameRaw) {
-									this.recacheInboxMessageList();
+									Remote.messageList(null, {Folder: getFolderInboxName()}, true);
 								}
 							}
 						}
@@ -604,7 +600,7 @@ class AppUser extends AbstractApp {
 						folder.messageCountUnread(folder.messageCountUnread() - alreadyUnread);
 					}
 
-					Remote.messageSetSeen(()=>0, sFolderFullNameRaw, rootUids, true);
+					Remote.messageSetSeen(null, sFolderFullNameRaw, rootUids, true);
 					break;
 
 				case MessageSetAction.UnsetSeen:
@@ -617,7 +613,7 @@ class AppUser extends AbstractApp {
 						folder.messageCountUnread(folder.messageCountUnread() - alreadyUnread + rootUids.length);
 					}
 
-					Remote.messageSetSeen(()=>0, sFolderFullNameRaw, rootUids, false);
+					Remote.messageSetSeen(null, sFolderFullNameRaw, rootUids, false);
 					break;
 
 				case MessageSetAction.SetFlag:
@@ -625,7 +621,7 @@ class AppUser extends AbstractApp {
 						MessageFlagsCache.storeBySetAction(sFolderFullNameRaw, sSubUid, iSetAction)
 					);
 
-					Remote.messageSetFlagged(()=>0, sFolderFullNameRaw, rootUids, true);
+					Remote.messageSetFlagged(null, sFolderFullNameRaw, rootUids, true);
 					break;
 
 				case MessageSetAction.UnsetFlag:
@@ -633,7 +629,7 @@ class AppUser extends AbstractApp {
 						MessageFlagsCache.storeBySetAction(sFolderFullNameRaw, sSubUid, iSetAction)
 					);
 
-					Remote.messageSetFlagged(()=>0, sFolderFullNameRaw, rootUids, false);
+					Remote.messageSetFlagged(null, sFolderFullNameRaw, rootUids, false);
 					break;
 				// no default
 			}
@@ -769,7 +765,7 @@ class AppUser extends AbstractApp {
 							FolderUserStore.hasCapability('LIST-STATUS') || this.folderInformationMultiply(true);
 						}, 1000);
 
-						setTimeout(() => Remote.appDelayStart(()=>0), 35000);
+						setTimeout(() => Remote.appDelayStart(null), 35000);
 
 						// When auto-login is active
 						if (
diff --git a/dev/Settings/User/Folders.js b/dev/Settings/User/Folders.js
index 3dc3e21e3..6fd2df70b 100644
--- a/dev/Settings/User/Folders.js
+++ b/dev/Settings/User/Folders.js
@@ -143,20 +143,20 @@ export class FoldersUserSettings /*extends AbstractViewSettings*/ {
 	toggleFolderKolabType(folder, event) {
 		let type = event.target.value;
 		// TODO: append '.default' ?
-		Remote.folderSetMetadata(()=>0, folder.fullNameRaw, FolderMetadataKeys.KolabFolderType, type);
+		Remote.folderSetMetadata(null, folder.fullNameRaw, FolderMetadataKeys.KolabFolderType, type);
 		folder.kolabType(type);
 	}
 
 	toggleFolderSubscription(folder) {
 		let subscribe = !folder.subscribed();
 		Local.set(ClientSideKeyName.FoldersLashHash, '');
-		Remote.folderSetSubscribe(()=>0, folder.fullNameRaw, subscribe);
+		Remote.folderSetSubscribe(null, folder.fullNameRaw, subscribe);
 		folder.subscribed(subscribe);
 	}
 
 	toggleFolderCheckable(folder) {
 		let checkable = !folder.checkable();
-		Remote.folderSetCheckable(()=>0, folder.fullNameRaw, checkable);
+		Remote.folderSetCheckable(null, folder.fullNameRaw, checkable);
 		folder.checkable(checkable);
 	}
 }
diff --git a/dev/Stores/User/Folder.js b/dev/Stores/User/Folder.js
index 8b600d885..5b8e89bb0 100644
--- a/dev/Stores/User/Folder.js
+++ b/dev/Stores/User/Folder.js
@@ -171,6 +171,6 @@ export const FolderUserStore = new class {
 			ArchiveFolder: FolderUserStore.archiveFolder()
 		};
 		Object.entries(folders).forEach(([k,v])=>Settings.set(k,v));
-		rl.app.Remote.saveSystemFolders(()=>0, folders);
+		rl.app.Remote.saveSystemFolders(null, folders);
 	}
 };
diff --git a/dev/View/User/MailBox/MessageList.js b/dev/View/User/MailBox/MessageList.js
index 6db0da53f..e3c44f372 100644
--- a/dev/View/User/MailBox/MessageList.js
+++ b/dev/View/User/MailBox/MessageList.js
@@ -490,7 +490,7 @@ export class MailMessageList extends AbstractViewRight {
 							MessageFlagsCache.clearFolder(sFolderFullNameRaw);
 						}
 
-						Remote.messageSetSeenToAll(()=>0, sFolderFullNameRaw, true, iThreadUid ? uids : null);
+						Remote.messageSetSeenToAll(null, sFolderFullNameRaw, true, iThreadUid ? uids : null);
 						break;
 					case MessageSetAction.UnsetSeen:
 						folder = getFolderFromCacheList(sFolderFullNameRaw);
@@ -516,7 +516,7 @@ export class MailMessageList extends AbstractViewRight {
 							MessageFlagsCache.clearFolder(sFolderFullNameRaw);
 						}
 
-						Remote.messageSetSeenToAll(()=>0, sFolderFullNameRaw, false, iThreadUid ? uids : null);
+						Remote.messageSetSeenToAll(null, sFolderFullNameRaw, false, iThreadUid ? uids : null);
 						break;
 					// no default
 				}
diff --git a/dev/View/User/MailBox/MessageView.js b/dev/View/User/MailBox/MessageView.js
index 819534f3a..58c679040 100644
--- a/dev/View/User/MailBox/MessageView.js
+++ b/dev/View/User/MailBox/MessageView.js
@@ -609,7 +609,7 @@ export class MailMessageView extends AbstractViewRight {
 		let oMessage = MessageUserStore.message()
 		if (oMessage && oMessage.readReceipt()) {
 			Remote.sendReadReceiptMessage(
-				()=>0,
+				null,
 				oMessage.folder,
 				oMessage.uid,
 				oMessage.readReceipt(),