- `spec.usages` is now required, may not contain duplicate values, and must only contain known usages
  - `status.conditions` may not contain duplicate types
  - `status.conditions[*].status` is now required

- EndpointSlice controllers are less likely to create duplicate EndpointSlices. ([#100103](https://github.com/kubernetes/kubernetes/pull/100103), [@robscott](https://github.com/robscott)) [SIG Apps and Network]

### SIG Storage

- The AllowedTopologies field inside StorageClass is now validated against set and map semantics. Specifically, there cannot be duplicate TopologySelectorTerms, MatchLabelExpressions keys, or TopologySelectorLabelRequirement Values. ([#66843](https://github.com/kubernetes/kubernetes/pull/66843), [@verult](https://github.com/verult))

- Improvements were made to `kubeadm reset` related to cleaning  etcd and notifying the user about the state of iptables.
- kubeadm commands now print warnings if input YAML documents contain unknown or duplicate fields.
- kubeadm now properly recognizes Docker 18.09.0 and newer, but still treats 18.06 as the default supported version.
- kubeadm now automatically sets the `--pod-infra-container-image` flag when starting the kubelet.

"getById","getElementsByName","disconnectedMatch","cssHas","querySelector","filter","attrId","getAttributeNode","tag","className","input","innerHTML","compare","sortDetached","expr","elements","matchesSelector","attr","attrHandle","uniqueSort","duplicates","sortStable","createPseudo","relative",">"," ","+","~","preFilter","excess","unquoted","nodeNameSelector","expectedNodeName","pattern","operator","check","result","what","_argument","simple","forward","ofType","_context","xml","outerCache","no...

paragraphs\n//\n// Similarly, the top margin on `<p>`s get reset. However, we also reset the\n// bottom margin to use `rem` units instead of `em`.\np {\n  margin-top: 0;\n  margin-bottom: $paragraph-margin-bottom;\n}\n\n// Abbreviations\n//\n// 1. Duplicate behavior to the data-* attribute for our tooltip plugin\n// 2. Add the correct text decoration in Chrome, Edge, IE, Opera, and Safari.\n// 3. Add explicit cursor to indicate changed behavior.\n// 4. Remove the bottom border in Firefox 39-.\n// 5....

* Bumps metrics-server version to v0.3.6 with following bugfix: ([#83907](https://github.com/kubernetes/kubernetes/pull/83907), [@olagacek](https://github.com/olagacek))
        *  Don't break metric storage when duplicate pod metrics encountered causing hpa to fail
* kube-apiserver: Fixed a regression accepting patch requests > 1MB ([#84963](https://github.com/kubernetes/kubernetes/pull/84963), [@liggitt](https://github.com/liggitt))

In particular, the following storage features are moving to GA in Kubernetes 1.18:
- Raw Block Support: Allow volumes to be surfaced as block devices inside containers instead of just mounted filesystems.
- Volume Cloning: Duplicate a PersistentVolumeClaim and underlying storage volume using the Kubernetes API via CSI.
- CSIDriver Kubernetes API Object: Simplifies CSI driver discovery and allows CSI Drivers to customize Kubernetes behavior.

- Remove the deprecated flag `--generator` from `kubectl create deployment` command. ([#99915](https://github.com/kubernetes/kubernetes/pull/99915), [@BLasan](https://github.com/BLasan))
- Remove the duplicate packet import. ([#101187](https://github.com/kubernetes/kubernetes/pull/101187), [@chuntaochen](https://github.com/chuntaochen))

paragraphs\n//\n// Similarly, the top margin on `<p>`s get reset. However, we also reset the\n// bottom margin to use `rem` units instead of `em`.\np {\n  margin-top: 0;\n  margin-bottom: $paragraph-margin-bottom;\n}\n\n// Abbreviations\n//\n// 1. Duplicate behavior to the data-* attribute for our tooltip plugin\n// 2. Add the correct text decoration in Chrome, Edge, IE, Opera, and Safari.\n// 3. Add explicit cursor to indicate changed behavior.\n// 4. Remove the bottom border in Firefox 39-.\n// 5....