incorrectly placed a pod in the "unschedulable" queue instead of the "backoff" queue. This happened when some plugin previously declared the pod as "unschedulable" and then in a later attempt encounters some other error. Scheduling of that pod then got delayed by up to five minutes, after which periodic flushing moved the pod back into the "active" queue. ([#120334](https://github.com/kubernetes/kubernetes/pull/120334), [@pohly](https://github.com/pohly)) [SIG Scheduling]

### Other (Cleanup...

message NodeCondition {
  // Type of node condition.
  optional string type = 1;

  // Status of the condition, one of True, False, Unknown.
  optional string status = 2;

  // Last time we got an update on a given condition.
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.Time lastHeartbeatTime = 3;

  // Last time the condition transit from one status to another.
  // +optional

	"type":               "Type of node condition.",
	"status":             "Status of the condition, one of True, False, Unknown.",
	"lastHeartbeatTime":  "Last time we got an update on a given condition.",
	"lastTransitionTime": "Last time the condition transit from one status to another.",
	"reason":             "(brief) reason for the condition's last transition.",

			key := matchExpression.Key
			if i, ok := labelKeysMap[key]; ok && labelSelectorKeys.Has(key) {
				// Before validateLabelKeysWithSelector is called, the labelSelector has already got the selector created from matchLabelKeys.
				// Here, we found the duplicate key in labelSelector and the key is specified in labelKeys.

message NodeCondition {
  // Type of node condition.
  optional string type = 1;

  // Status of the condition, one of True, False, Unknown.
  optional string status = 2;

  // Last time we got an update on a given condition.
  // +optional
  optional .k8s.io.apimachinery.pkg.apis.meta.v1.Time lastHeartbeatTime = 3;

  // Last time the condition transit from one status to another.
  // +optional

* not allowing "kubectl edit <resource>" when you got an empty list ([#50205](https://github.com/kubernetes/kubernetes/pull/50205), [@dixudx](https://github.com/dixudx))