diff --git a/modules/juce_gui_basics/native/juce_Windowing_windows.cpp b/modules/juce_gui_basics/native/juce_Windowing_windows.cpp
index 2e2eec13ad..b5cc9af334 100644
--- a/modules/juce_gui_basics/native/juce_Windowing_windows.cpp
+++ b/modules/juce_gui_basics/native/juce_Windowing_windows.cpp
@@ -1527,7 +1527,7 @@ public:
 
     std::optional<BorderSize<int>> getCustomBorderSize() const
     {
-        if (hasTitleBar() || (styleFlags & windowIsTemporary) != 0)
+        if (hasTitleBar() || (styleFlags & windowIsTemporary) != 0 || isFullScreen())
             return {};
 
         return BorderSize<int> { 0, 0, 0, 0 };