diff --git a/src/slic3r/GUI/Plater.cpp b/src/slic3r/GUI/Plater.cpp
index 8e7c2fa90..06d49d9be 100644
--- a/src/slic3r/GUI/Plater.cpp
+++ b/src/slic3r/GUI/Plater.cpp
@@ -5591,7 +5591,8 @@ void Plater::priv::set_project_name(const wxString& project_name)
     wxGetApp().mainframe->topbar()->SetTitle(m_project_name);
 #else
     wxGetApp().mainframe->SetTitle(m_project_name);
-    wxGetApp().mainframe->update_title_colour_after_set_title();
+    if (!m_project_name.IsEmpty())
+        wxGetApp().mainframe->update_title_colour_after_set_title();
 #endif
 }
 
diff --git a/src/slic3r/Utils/MacDarkMode.mm b/src/slic3r/Utils/MacDarkMode.mm
index bd02889b9..36889160f 100644
--- a/src/slic3r/Utils/MacDarkMode.mm
+++ b/src/slic3r/Utils/MacDarkMode.mm
@@ -17,7 +17,7 @@
 namespace Slic3r {
 namespace GUI {
 
-NSTextField* mainframe_text_field;
+NSTextField* mainframe_text_field = nil;
 
 bool mac_dark_mode()
 {