diff --git a/Backend/Appearance.cs b/Backend/Appearance.cs
index f557268..c5d9926 100644
--- a/Backend/Appearance.cs
+++ b/Backend/Appearance.cs
@@ -400,9 +400,9 @@ public Proto.Appearances.AppearanceFlagMarket GetOrCreateMarketFlags()
                 handleFlag(change, flags.Height.HasElevation, ItemTypeFlag.HasElevation, "Height.HasElevation");
             }
 
-            // Both expire and expireStop map to ClientDuration.
-            bool hasExpiryToggle = (flags.Expire || flags.Expirestop);
-            handleFlag(change, hasExpiryToggle, ItemTypeFlag.ClientDuration, "expire | expireStop");
+            // All of expire, expireStop and clockExpire map to ClientDuration (as of 12.90).
+            bool hasExpiryToggle = (flags.Expire || flags.Expirestop || flags.Clockexpire);
+            handleFlag(change, hasExpiryToggle, ItemTypeFlag.ClientDuration, "expire | expireStop | clockExpire");
 
             return change.changes.Count > 0 ? change : null;
         }
diff --git a/LapisItemEditor/LapisItemEditor.csproj b/LapisItemEditor/LapisItemEditor.csproj
index 1b7ad17..9d4c8ad 100644
--- a/LapisItemEditor/LapisItemEditor.csproj
+++ b/LapisItemEditor/LapisItemEditor.csproj
@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <OutputType>WinExe</OutputType>
+    <OutputType>Exe</OutputType>
     <TargetFramework>net6.0</TargetFramework>
     <Nullable>enable</Nullable>
     <RootNamespace>LapisItemEditor</RootNamespace>
diff --git a/LapisItemEditor/ViewModels/Main/ItemPropertiesViewModel.cs b/LapisItemEditor/ViewModels/Main/ItemPropertiesViewModel.cs
index 7ec63b8..8f288da 100644
--- a/LapisItemEditor/ViewModels/Main/ItemPropertiesViewModel.cs
+++ b/LapisItemEditor/ViewModels/Main/ItemPropertiesViewModel.cs
@@ -346,6 +346,7 @@ public class ItemPropertiesViewModel : ViewModelBase
         private bool hasWearout;
         private bool hasExpire;
         private bool hasExpireStop;
+        private bool hasClockExpire;
         private bool hasTradeAs;
         private bool hasShowAs;
         private bool hasMinimumLevel;
@@ -429,6 +430,7 @@ public ItemPropertiesViewModel()
                     HasWearout = false;
                     HasExpire = false;
                     HasExpireStop = false;
+                    HasClockExpire = false;
                     HasTradeAs = false;
                     HasShowAs = false;
                     HasMinimumLevel = false;
@@ -578,6 +580,7 @@ public ItemPropertiesViewModel()
                     FullBank = _flags.Fullbank;
                     HasExpire = _flags.Expire;
                     HasExpireStop = _flags.Expirestop;
+                    HasClockExpire = _flags.Clockexpire;
 
                     HasWearout = _flags.Wearout;
 
@@ -922,6 +925,14 @@ public ItemPropertiesViewModel()
                 }
             });
 
+            this.WhenAnyValue(x => x.hasClockExpire).Subscribe(value =>
+            {
+                if (flags != null)
+                {
+                    flags.Clockexpire = value;
+                }
+            });
+
             this.WhenAnyValue(x => x.IgnoreLook).Subscribe(value =>
             {
                 if (flags != null)
@@ -1053,6 +1064,7 @@ public ItemPropertiesViewModel()
         public bool HasWearout { get => hasWearout; set => this.RaiseAndSetIfChanged(ref hasWearout, value); }
         public bool HasExpire { get => hasExpire; set => this.RaiseAndSetIfChanged(ref hasExpire, value); }
         public bool HasExpireStop { get => hasExpireStop; set => this.RaiseAndSetIfChanged(ref hasExpireStop, value); }
+        public bool HasClockExpire { get => hasClockExpire; set => this.RaiseAndSetIfChanged(ref hasClockExpire, value); }
         public bool HasTradeAs { get => hasTradeAs; set => this.RaiseAndSetIfChanged(ref hasTradeAs, value); }
         public bool HasShowAs { get => hasShowAs; set => this.RaiseAndSetIfChanged(ref hasShowAs, value); }
         public bool HasMinimumLevel { get => hasMinimumLevel; set => this.RaiseAndSetIfChanged(ref hasMinimumLevel, value); }
diff --git a/LapisItemEditor/Views/Main/ItemPropertiesView.axaml b/LapisItemEditor/Views/Main/ItemPropertiesView.axaml
index 3123b49..fd587ee 100644
--- a/LapisItemEditor/Views/Main/ItemPropertiesView.axaml
+++ b/LapisItemEditor/Views/Main/ItemPropertiesView.axaml
@@ -134,7 +134,7 @@
     </StackPanel>
 
 		<!-- Second column -->
-    <StackPanel Grid.Row="1" Grid.Column="1" Orientation="Vertical" MinHeight="200">
+    <StackPanel Grid.Row="1" Grid.Column="1" Orientation="Vertical" MinHeight="200" Margin="20,0,20,0">
         <Grid RowDefinitions="*,*" Margin="0 0 9 0">
             <TextBlock Grid.Row="0" Padding="4 2 4 2">Hangable Hook Type</TextBlock>
             <ComboBox Grid.Row="1" Items="{Binding HangableHookTypes}" SelectedItem="{Binding HangableHookType, Mode=TwoWay}" SelectedIndex="0">
@@ -189,7 +189,7 @@
     </StackPanel>
 
         <!-- Third column -->
-    <StackPanel Grid.Row="1" Grid.Column="2" Orientation="Vertical" MinHeight="200">
+    <StackPanel Grid.Row="1" Grid.Column="2" Orientation="Vertical" MinHeight="200" Margin="20,0,20,0">
         <StackPanel Orientation="Horizontal">
             <CheckBox IsChecked="{Binding Height, Mode=TwoWay}">Height</CheckBox>
             <PathIcon Classes="question-mark" ToolTip.Tip="If an object offsets objects that sit on top of it (like a table or a parcel)." />
@@ -291,7 +291,12 @@
 
         <StackPanel Orientation="Horizontal" Margin="0,4,0,0">
             <CheckBox IsChecked="{Binding HasExpireStop, Mode=TwoWay}" VerticalAlignment="Center" Margin="0,0,4,0">Expire stop</CheckBox>
-            <PathIcon Classes="question-mark" ToolTip.Tip="If the thing has a stop expire"/>
+            <PathIcon Classes="question-mark" ToolTip.Tip="If the thing has flag expirestop"/>
+        </StackPanel>
+
+        <StackPanel Orientation="Horizontal" Margin="0,4,0,0">
+            <CheckBox IsChecked="{Binding HasClockExpire, Mode=TwoWay}" VerticalAlignment="Center" Margin="0,0,4,0">Clock expire</CheckBox>
+            <PathIcon Classes="question-mark" ToolTip.Tip="If the thing has flag clockexpire"/>
         </StackPanel>
 
     </StackPanel>
diff --git a/LapisItemEditor/Views/Main/MainWindow.axaml.cs b/LapisItemEditor/Views/Main/MainWindow.axaml.cs
index c3fbfec..fe79efd 100644
--- a/LapisItemEditor/Views/Main/MainWindow.axaml.cs
+++ b/LapisItemEditor/Views/Main/MainWindow.axaml.cs
@@ -1,6 +1,3 @@
-using System;
-using System.Diagnostics;
-using System.IO;
 using Avalonia.Controls;
 using Avalonia.Input;
 using Avalonia.Markup.Xaml;