Use KIconTheme::initTheme()

See https://invent.kde.org/frameworks/kiconthemes/-/issues/3 for more
information of what this does

CMakeLists.txt

@@ -55,7 +55,7 @@ if (LINUX)
     find_package(Qt6 ${QT_MIN_VERSION} REQUIRED NO_MODULE COMPONENTS DBus)
 endif ()
 
-find_package(KF6 ${KF_MIN_VERSION} REQUIRED COMPONENTS Kirigami I18n Config CoreAddons Archive)
+find_package(KF6 ${KF_MIN_VERSION} REQUIRED COMPONENTS Kirigami I18n Config CoreAddons Archive IconThemes)
 find_package(KF6KirigamiAddons 1.2.1 REQUIRED)
 find_package(QCoro6 REQUIRED COMPONENTS Core Network Qml)
 qcoro_enable_coroutines()

launcher/CMakeLists.txt

@@ -3,7 +3,7 @@
 
 add_library(astra_static STATIC)
 
-ecm_add_qml_module(astra_static
+ecm_add_qml_module(astra_static GENERATE_PLUGIN_SOURCE
         URI zone.xiv.astra
         VERSION 1.0)
 
@@ -183,7 +183,8 @@ target_link_libraries(astra PRIVATE
         KDAB::kdsingleapplication
         Qt6::Widgets
         Qt6::QuickControls2
-        KF6::Kirigami)
+        KF6::Kirigami
+        KF6::IconThemes)
 
 if (BUILD_WEBVIEW)
     target_link_libraries(astra PRIVATE
@@ -208,7 +209,6 @@ install(TARGETS astra ${KF6_INSTALL_TARGETS_DEFAULT_ARGS})
 
 ecm_add_app_icon(astra
         ICONS
-        ${CMAKE_SOURCE_DIR}/zone.xiv.astra.svg
         ${CMAKE_SOURCE_DIR}/resources/16-astra.png
         ${CMAKE_SOURCE_DIR}/resources/32-astra.png
         ${CMAKE_SOURCE_DIR}/resources/48-astra.png

launcher/src/main.cpp

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 #include <KAboutData>
+#include <KIconTheme>
 #include <KLocalizedContext>
 #include <KLocalizedString>
 #include <QGuiApplication> // NOTE: do not remove this, if your IDE suggests to do so
@@ -32,10 +33,7 @@ int main(int argc, char *argv[])
     QtWebView::initialize();
 #endif
 
-#ifdef Q_OS_WIN
-    BreezeIcons::initIcons();
-    QIcon::setThemeName(QStringLiteral("Breeze"));
-#endif
+    KIconTheme::initTheme();
 
     if (Utility::isSteamDeck()) {
         qputenv("QT_SCALE_FACTOR", "1.25");