diff --git a/include/SDL3/SDL_video.h b/include/SDL3/SDL_video.h
index 04846e0245..d727457191 100644
--- a/include/SDL3/SDL_video.h
+++ b/include/SDL3/SDL_video.h
@@ -3234,6 +3234,9 @@ extern SDL_DECLSPEC bool SDLCALL SDL_GL_GetAttribute(SDL_GLAttr attr, int *value
  * The OpenGL context will be created with the current states set through
  * SDL_GL_SetAttribute().
  *
+ * The SDL_Window specified must have been created with the SDL_WINDOW_OPENGL
+ * flag, or context creation will fail.
+ *
  * Windows users new to OpenGL should note that, for historical reasons, GL
  * functions added after OpenGL version 1.1 are not available by default.
  * Those functions must be loaded at run-time, either with an OpenGL