diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 121bc7c4..6f5ace30 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -77,10 +77,10 @@ jobs:
         with:
           arch: x64
 
-      - name: Install Qt 6.8
+      - name: Install Qt 6.8.1
         uses: jurplel/install-qt-action@v4
         with:
-          version: "6.8.0"
+          version: "6.8.1"
           host: windows
           target: desktop
           arch: win64_msvc2022_64
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 823b1341..037c4998 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -135,10 +135,10 @@ jobs:
       - name: Install NSIS
         run: choco install nsis --yes --no-progress
 
-      - name: Install Qt 6.8
+      - name: Install Qt 6.8.1
         uses: jurplel/install-qt-action@v4
         with:
-          version: "6.8.0"
+          version: "6.8.1"
           host: windows
           target: desktop
           arch: win64_msvc2022_64
diff --git a/BUILDING_WINDOWS.md b/BUILDING_WINDOWS.md
index 74dbf39d..4cc64ce0 100644
--- a/BUILDING_WINDOWS.md
+++ b/BUILDING_WINDOWS.md
@@ -41,7 +41,7 @@ files, in addition to the space requested by each installer.
 | --- | --- |
 | [Git for Windows](https://git-scm.com/downloads/win) | Use the normal installer and allow Git to be used from the command line. |
 | [Visual Studio Build Tools](https://visualstudio.microsoft.com/downloads/#build-tools-for-visual-studio) or Visual Studio Community | Select **Desktop development with C++**, including **MSVC x64/x86 build tools**, a **Windows SDK**, and **C++ CMake tools for Windows**. The full editor is optional. |
-| [Qt Online Installer](https://www.qt.io/development/download-open-source) | Choose the **MSVC 2022 64-bit** desktop component. The tested version is **Qt 6.11.1**. Do not choose MinGW or ARM64. |
+| [Qt Online Installer](https://www.qt.io/development/download-open-source) | Choose the **MSVC 2022 64-bit** desktop component. **Qt 6.8.1 or newer is required**; 6.8.0 has a Windows font-matching bug. The tested version is **Qt 6.11.1**. Do not choose MinGW or ARM64. |
 | [LilyPond for Windows](https://lilypond.org/download.html) | Extract the **entire** Windows x86_64 ZIP. The tested version is **2.26.0**. Keep its `bin`, `lib`, and `share` folders together. |
 
 The Visual Studio CMake component supplies CMake and Ninja. This project needs
diff --git a/LASSIE/CMakeLists.txt b/LASSIE/CMakeLists.txt
index 9ab8c689..e4b053a8 100644
--- a/LASSIE/CMakeLists.txt
+++ b/LASSIE/CMakeLists.txt
@@ -4,6 +4,11 @@ project(LASSIE)
 message(STATUS "== LASSIE ==")
 
 find_package(Qt6 REQUIRED COMPONENTS Widgets Core Xml Network)
+if(WIN32 AND Qt6_VERSION VERSION_LESS "6.8.1")
+    message(FATAL_ERROR
+        "Windows builds require Qt 6.8.1 or newer. Qt 6.8.0 can substitute "
+        "the wrong font family for the Windows system font.")
+endif()
 
 set(CMAKE_AUTOUIC ON)
 set(CMAKE_AUTOMOC ON)
@@ -104,6 +109,20 @@ target_include_directories(LASSIE PRIVATE
     ${CMAKE_SOURCE_DIR}/LASS/src
 )
 
+if(NOT APPLE)
+    qt_add_resources(LASSIE "app_icons"
+        PREFIX "/icons"
+        BASE "${CMAKE_SOURCE_DIR}/packaging/linux"
+        FILES "${CMAKE_SOURCE_DIR}/packaging/linux/LASSIE.png"
+    )
+endif()
+
+if(WIN32)
+    configure_file("${CMAKE_SOURCE_DIR}/packaging/windows/LASSIE.rc.in"
+        "${CMAKE_CURRENT_BINARY_DIR}/LASSIE.rc" @ONLY)
+    target_sources(LASSIE PRIVATE "${CMAKE_CURRENT_BINARY_DIR}/LASSIE.rc")
+endif()
+
 set(LASSIE_ICON_MACOS "${CMAKE_SOURCE_DIR}/packaging/macos/LASSIE.icns")
 if(APPLE AND EXISTS "${LASSIE_ICON_MACOS}")
     target_sources(LASSIE PRIVATE "${LASSIE_ICON_MACOS}")
@@ -131,6 +150,13 @@ install(TARGETS LASSIE
     RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR} COMPONENT Runtime
 )
 
+if(UNIX AND NOT APPLE)
+    install(FILES "${CMAKE_SOURCE_DIR}/packaging/linux/LASSIE.desktop"
+        DESTINATION "${CMAKE_INSTALL_DATADIR}/applications" COMPONENT Runtime)
+    install(FILES "${CMAKE_SOURCE_DIR}/packaging/linux/LASSIE.png"
+        DESTINATION "${CMAKE_INSTALL_DATADIR}/icons/hicolor/256x256/apps" COMPONENT Runtime)
+endif()
+
 if(QT_VERSION_MAJOR EQUAL 6)
     qt_finalize_executable(LASSIE)
 endif()
@@ -181,6 +207,21 @@ endif()
 
 if(BUILD_TESTING)
     target_compile_definitions(LASSIE PRIVATE DISSCO_ENABLE_UI_LAYOUT_TESTS)
+    if(NOT APPLE)
+        add_test(NAME LASSIE.ApplicationIdentity COMMAND LASSIE)
+        set_tests_properties(LASSIE.ApplicationIdentity PROPERTIES
+            ENVIRONMENT "QT_QPA_PLATFORM=offscreen;QT_FORCE_STDERR_LOGGING=1;DISSCO_TEST_APPLICATION_IDENTITY=1"
+            TIMEOUT 10
+        )
+    endif()
+    if(WIN32)
+        add_test(NAME LASSIE.WindowsSystemFont COMMAND LASSIE)
+        set_tests_properties(LASSIE.WindowsSystemFont PROPERTIES
+            ENVIRONMENT "QT_QPA_PLATFORM=windows;QT_FORCE_STDERR_LOGGING=1;DISSCO_TEST_WINDOWS_FONT=1"
+            SKIP_RETURN_CODE 77
+            TIMEOUT 10
+        )
+    endif()
     add_test(NAME LASSIE.EnvelopeLegendLayout
         COMMAND LASSIE
     )
diff --git a/LASSIE/src/main.cpp b/LASSIE/src/main.cpp
index 18c5966b..5ba5ce2e 100644
--- a/LASSIE/src/main.cpp
+++ b/LASSIE/src/main.cpp
@@ -2,10 +2,19 @@
 
 #include <QApplication>
 #include <QFile>
+#include <QIcon>
 #ifdef DISSCO_ENABLE_UI_LAYOUT_TESTS
 #include <QDebug>
+#include <QFontDatabase>
+#include <QFontInfo>
 #include <QLabel>
 #include <QLayout>
+#ifdef Q_OS_WIN
+#ifndef NOGDI
+#define NOGDI
+#endif
+#include <qt_windows.h>
+#endif
 #include "windows/EnvelopeLibraryWindow.hpp"
 #endif
 #include "widgets/ComboBoxWheelGuard.hpp"
@@ -24,10 +33,56 @@ int main(int argc, char *argv[])
     QCoreApplication::setApplicationName("LASSIE");
 
     QApplication a(argc, argv);
+#ifndef Q_OS_MACOS
+    a.setWindowIcon(QIcon(QStringLiteral(":/icons/LASSIE.png")));
+#endif
+#ifdef Q_OS_LINUX
+    a.setDesktopFileName(QStringLiteral("LASSIE"));
+#endif
     ComboBoxWheelGuard comboBoxWheelGuard(a);
     TextOverflowDisplayPolicy textOverflowDisplayPolicy(a);
 
 #ifdef DISSCO_ENABLE_UI_LAYOUT_TESTS
+#ifdef Q_OS_WIN
+    if (qEnvironmentVariableIsSet("DISSCO_TEST_WINDOWS_FONT")) {
+        const QFont font = a.font();
+        if (!QFontDatabase::families().contains(font.family(), Qt::CaseInsensitive)) {
+            qWarning() << "Skipping font check: system font uses an unlisted alias"
+                       << font.family();
+            return 77;
+        }
+        const QString resolvedFamily = QFontInfo(font).family();
+        if (font.family().compare(resolvedFamily, Qt::CaseInsensitive) != 0) {
+            qCritical() << "Installed Windows system font was substituted:"
+                        << "requested" << font.family() << "resolved" << resolvedFamily;
+            return 1;
+        }
+        return 0;
+    }
+#endif
+
+    if (qEnvironmentVariableIsSet("DISSCO_TEST_APPLICATION_IDENTITY")) {
+        EnvelopeLibraryWindow window;
+        if (a.windowIcon().pixmap(32, 32).isNull()
+            || window.windowIcon().pixmap(32, 32).isNull()) {
+            qCritical() << "Application and top-level windows must have a usable icon";
+            return 1;
+        }
+#ifdef Q_OS_WIN
+        if (!FindResourceW(nullptr, MAKEINTRESOURCEW(1), RT_GROUP_ICON)) {
+            qCritical() << "Executable is missing its Windows application icon resource";
+            return 1;
+        }
+#endif
+#ifdef Q_OS_LINUX
+        if (a.desktopFileName() != QStringLiteral("LASSIE")) {
+            qCritical() << "Desktop identity must match LASSIE.desktop";
+            return 1;
+        }
+#endif
+        return 0;
+    }
+
     if (qEnvironmentVariableIsSet("DISSCO_TEST_ENVELOPE_LAYOUT")) {
         EnvelopeLibraryWindow window;
         window.ensurePolished();
diff --git a/packaging/windows/LASSIE.rc.in b/packaging/windows/LASSIE.rc.in
new file mode 100644
index 00000000..7a0d6292
--- /dev/null
+++ b/packaging/windows/LASSIE.rc.in
@@ -0,0 +1 @@
+1 ICON "@CMAKE_SOURCE_DIR@/packaging/windows/LASSIE.ico"