diff --git a/src/lib.rs b/src/lib.rs
index 7ebf16e..ddb0732 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -149,6 +149,9 @@ impl Platform {
             format,
             width:                         win_size.0 as u32,
             height:                        win_size.1 as u32,
+            // TODO: Mailbox ist nicht überall in caps.present_modes — bei
+            // unsupported Treibern panict configure(). Fifo wäre der sichere
+            // Vsync-Fallback. Erstmal beobachten.
             present_mode:                  if cfg.vsync { wgpu::PresentMode::Mailbox } else { wgpu::PresentMode::Immediate },
             alpha_mode:                    caps.alpha_modes[0],
             view_formats:                  vec![],