extensions status indicator in title bar

src/app_layout.cpp

@@ -815,6 +815,11 @@ void App::initLayout()
             version_label->set_text(g_version);
         }
 
+        if (auto x = layout[main_id]->find<NodeBorder>("ext-fbf"))
+        {
+            x->m_color = ShaderManager::ext_framebuffer_fetch ? glm::vec4(0, 1, 0, 1) : glm::vec4(1, 0, 0, 1);
+        }
+
         brush_update();
         
         TextureManager::load("data/paper.jpg");