diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5666f48..88e5ab7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 ## 1.6.2 (Unreleased)
 
 - Fixed rolled log files created with trailing sequence sometimes created on app startup ([#136](https://github.com/tetsuo13/TeamsStatusPub/issues/136))
+- Prevent multiple About windows ([#129](https://github.com/tetsuo13/TeamsStatusPub/issues/129))
 
 ## 1.6.1 (2024-08-28)
 
diff --git a/src/TeamsStatusPub/App.axaml.cs b/src/TeamsStatusPub/App.axaml.cs
index 4c42733..e1d4fd1 100644
--- a/src/TeamsStatusPub/App.axaml.cs
+++ b/src/TeamsStatusPub/App.axaml.cs
@@ -6,10 +6,11 @@
 using Avalonia.Markup.Xaml;
 using Microsoft.Extensions.DependencyInjection;
 using ReactiveUI;
-using TeamsStatusPub.ViewModels;
 using TeamsStatusPub.Core.Configuration;
 using TeamsStatusPub.Core.Services;
 using TeamsStatusPub.Core.Services.AvailabilityHandlers;
+using TeamsStatusPub.ViewModels;
+using TeamsStatusPub.Views;
 
 namespace TeamsStatusPub;
 
@@ -31,6 +32,7 @@ public override void OnFrameworkInitializationCompleted()
         collection.ConfigureAppServices();
         collection.AddTransient<AppViewModel>();
         collection.AddTransient<AboutViewModel>();
+        collection.AddSingleton<AboutWindow>();
 
         ServiceProvider = collection.BuildServiceProvider();
 
diff --git a/src/TeamsStatusPub/TeamsStatusPub.csproj b/src/TeamsStatusPub/TeamsStatusPub.csproj
index 0da77e9..ed3da19 100644
--- a/src/TeamsStatusPub/TeamsStatusPub.csproj
+++ b/src/TeamsStatusPub/TeamsStatusPub.csproj
@@ -2,7 +2,7 @@
   <PropertyGroup>
     <OutputType>WinExe</OutputType>
     <TargetFramework>net8.0</TargetFramework>
-    <RuntimeIdentifier>win-x64</RuntimeIdentifier>
+    <RuntimeIdentifiers>win-x64;linux-x64</RuntimeIdentifiers>
     <PlatformTarget>AnyCPU</PlatformTarget>
     <Nullable>enable</Nullable>
     <BuiltInComInteropSupport>true</BuiltInComInteropSupport>
diff --git a/src/TeamsStatusPub/ViewModels/AppViewModel.cs b/src/TeamsStatusPub/ViewModels/AppViewModel.cs
index 86a94df..1c20728 100644
--- a/src/TeamsStatusPub/ViewModels/AppViewModel.cs
+++ b/src/TeamsStatusPub/ViewModels/AppViewModel.cs
@@ -1,6 +1,7 @@
 using System.Reactive;
 using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
+using Microsoft.Extensions.DependencyInjection;
 using ReactiveUI;
 using TeamsStatusPub.Views;
 
@@ -15,8 +16,18 @@ public AppViewModel()
     {
         AboutCommand = ReactiveCommand.Create(() =>
         {
-            var view = new AboutWindow();
-            view.Show();
+            // Treat the about window like a dialog: only one instance should
+            // ever be shown.
+            var view = App.ServiceProvider.GetRequiredService<AboutWindow>();
+
+            if (!view.IsVisible)
+            {
+                view.Show();
+            }
+            else
+            {
+                view.Activate();
+            }
         });
 
         ExitCommand = ReactiveCommand.Create(() =>