drm: better describe add_connector usage
@@ -169,6 +169,11 @@ pub trait Surface {
/// Tries to add a new [`connector`](drm::control::connector)
/// to be used after the next commit.
///
+ /// **Warning**: You need to make sure, that the connector is not used with another surface
+ /// or was properly removed via `remove_connector` + `commit` before adding it to another surface.
+ /// Behavior if failing to do so is undefined, but might result in rendering errors or the connector
+ /// getting removed from the other surface without updating it's internal state.
+ ///
/// Fails if the `connector` is not compatible with the underlying [`crtc`](drm::control::crtc)
/// (e.g. no suitable [`encoder`](drm::control::encoder) may be found)
/// or is not compatible with the currently pending
