diff --git a/imgui.cpp b/imgui.cpp
index 908e8776..db367eef 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -10263,7 +10263,7 @@ void ImGui::ShowMetricsWindow(bool* p_open)
         ImGui::Text("NavDisableHighlight: %d, NavDisableMouseHover: %d", g.NavDisableHighlight, g.NavDisableMouseHover);
         ImGui::Text("NavWindowingTarget: '%s'", g.NavWindowingTarget ? g.NavWindowingTarget->Name : "NULL");
         ImGui::Text("DragDrop: %d, SourceId = 0x%08X, Payload \"%s\" (%d bytes)", g.DragDropActive, g.DragDropPayload.SourceId, g.DragDropPayload.DataType, g.DragDropPayload.DataSize);
-        ImGui::Text("MouseViewport: 0x%08X (UserHovered 0x%08X, LastHovered 0x%08X)", g.MouseViewport->ID, g.IO.MouseHoveredViewport, g.MouseLastHoveredViewport->ID);
+        ImGui::Text("MouseViewport: 0x%08X (UserHovered 0x%08X, LastHovered 0x%08X)", g.MouseViewport->ID, g.IO.MouseHoveredViewport, g.MouseLastHoveredViewport ? g.MouseLastHoveredViewport->ID : 0);
         ImGui::TreePop();
     }