Index: src/imgui/imgui_demo.cpp
--- src/imgui/imgui_demo.cpp.orig
+++ src/imgui/imgui_demo.cpp
@@ -5675,7 +5675,7 @@ void ImGui::ShowAboutWindow(bool* p_open)
 #ifdef _WIN64
         ImGui::Text("define: _WIN64");
 #endif
-#ifdef __linux__
+#if defined(__linux__) || defined(__OpenBSD__)
         ImGui::Text("define: __linux__");
 #endif
 #ifdef __APPLE__
