diff --git a/startkde/startkde.cmake b/startkde/startkde.cmake
--- a/startkde/startkde.cmake
+++ b/startkde/startkde.cmake
@@ -97,9 +97,18 @@
 #Set the QtQuickControls style to our own: for QtQuickControls1
 #it will fall back to Desktop, while it will use our own org.kde.desktop
 #for QtQuickControlsStyle and Kirigami
-export QT_QUICK_CONTROLS_1_STYLE=Desktop
 export QT_QUICK_CONTROLS_STYLE=org.kde.desktop
 
+# For Qt Quick Controls 1, there is no style with that name,
+# so override that explicitly with the default style to avoid
+# a warning on startup. However, simply setting it to "Desktop" does
+# not work, as QQuickControlSettings1 somehow messes that up and uses
+# the parent directory as import path, resulting in the wrong style "Base"
+# being used instead of the right one.
+# We can work around that by supplying a relative path to a nonexistent
+# directory, as it only looks at the file name in the end anyway...
+export QT_QUICK_CONTROLS_1_STYLE=non/existent/dir/Desktop
+
 # XCursor mouse theme needs to be applied here to work even for kded or ksmserver
 if test -n "$kcminputrc_mouse_cursortheme" -o -n "$kcminputrc_mouse_cursorsize" ; then
     @EXPORT_XCURSOR_PATH@
diff --git a/startkde/startplasma.cmake b/startkde/startplasma.cmake
--- a/startkde/startplasma.cmake
+++ b/startkde/startplasma.cmake
@@ -52,9 +52,18 @@
 #Set the QtQuickControls style to our own: for QtQuickControls1
 #it will fall back to Desktop, while it will use our own org.kde.desktop
 #for QtQuickControlsStyle and Kirigami
-export QT_QUICK_CONTROLS_1_STYLE=Desktop
 export QT_QUICK_CONTROLS_STYLE=org.kde.desktop
 
+# For Qt Quick Controls 1, there is no style with that name,
+# so override that explicitly with the default style to avoid
+# a warning on startup. However, simply setting it to "Desktop" does
+# not work, as QQuickControlSettings1 somehow messes that up and uses
+# the parent directory as import path, resulting in the wrong style "Base"
+# being used instead of the right one.
+# We can work around that by supplying a relative path to a nonexistent
+# directory, as it only looks at the file name in the end anyway...
+export QT_QUICK_CONTROLS_1_STYLE=non/existent/dir/Desktop
+
 #In wayland we want Plasma to use Qt's scaling
 export PLASMA_USE_QT_SCALING=1