diff --git a/src/slic3r/GUI/GUI_App.cpp b/src/slic3r/GUI/GUI_App.cpp
index 8940e13e6e..636ba985f5 100644
--- a/src/slic3r/GUI/GUI_App.cpp
+++ b/src/slic3r/GUI/GUI_App.cpp
@@ -3232,9 +3232,16 @@ bool GUI_App::on_init_inner()
 #ifdef _MSW_DARK_MODE
 
 #ifndef __WINDOWS__
+    // The label colours and the dark mode flag were set above from the saved mode. When the system theme
+    // differs from it, refresh them, or dialogs that map their colours stay in the old mode for this session.
+    const bool saved_dark_mode = dark_mode();
     wxSystemAppearance app = wxSystemSettings::GetAppearance();
     GUI::wxGetApp().app_config->set("dark_color_mode", app.IsDark() ? "1" : "0");
     GUI::wxGetApp().app_config->save();
+    if (dark_mode() != saved_dark_mode) {
+        init_label_colours();
+        Update_dark_mode_flag();
+    }
 #endif // __APPLE__