diff --git a/src/win32_init.c b/src/win32_init.c
index 18f60d38..885f32fa 100644
--- a/src/win32_init.c
+++ b/src/win32_init.c
@@ -503,6 +503,8 @@ void _glfwUpdateKeyNamesWin32(void)
 
         if (length == -1)
         {
+            // This is a dead key, so we need a second simulated key press
+            // to make it output its own character (usually a diacritic)
             length = ToUnicode(vk, scancode, state,
                                chars, sizeof(chars) / sizeof(WCHAR),
                                0);