// - the object is encrypted using SSE-C and two different SSE-C keys are present
	// - the object is encrypted using SSE-S3 and the SSE-S3 header is present
	// - the object storage class is not changing
	// then execute a key rotation.
	if cpSrcDstSame && (sseCopyC && sseC) && !chStorageClass {
		oldKey, err = ParseSSECopyCustomerRequest(r.Header, srcInfo.UserDefined)
		if err != nil {

		// request is supported. At the same time, we cannot allow adding
		// two delete markers on top of any object. To avoid this situation,
		// we will sort deletions to execute existing deletion first,
		// then add only one delete marker if requested
		sort.SliceStable(fivs.Versions, func(i, j int) bool {
			return !fivs.Versions[i].Deleted
		})