- When updating a CRD, per-expression cost limit check are now skipped for `x-kubernetes-validations` rules of versions that are not mutated. ([#121460](https://github.com/kubernetes/kubernetes/pull/121460), [@jiahuif](https://github.com/jiahuif))

but generally, just as she had got its neck nicely straightened
out, and was going to give the hedgehog a blow with its head, it
WOULD twist itself round and look up in her face, with such a
puzzled expression that she could not help bursting out laughing:
and when she had got its head down, and was going to begin again,
it was very provoking to find that the hedgehog had unrolled

- Added enforcement of an upper cost bound for DRA evaluations of CEL. The API server and scheduler now enforce an upper bound on the cost and runtime steps required for evaluating a CEL expression. ([#128101](https://github.com/kubernetes/kubernetes/pull/128101), [@pohly](https://github.com/pohly)) [SIG API Machinery and Node]

  Other Ingress API updates:
  - backends can now be resource or service backends
  - `path` is no longer required to be a valid regular expression ([#89778](https://github.com/kubernetes/kubernetes/pull/89778), [@cmluciano](https://github.com/cmluciano)) [SIG API Machinery, Apps, CLI, Network and Testing]

  return Boolean(SAFE_URL_PATTERN.test(attr.nodeValue) || DATA_URL_PATTERN.test(attr.nodeValue))\n    }\n\n    return true\n  }\n\n  const regExp = allowedAttributeList.filter(attrRegex => attrRegex instanceof RegExp)\n\n  // Check if a regular expression validates the attribute.\n  for (let i = 0, len = regExp.length; i < len; i++) {\n    if (regExp[i].test(attrName)) {\n      return true\n    }\n  }\n\n  return false\n}\n\nexport function sanitizeHtml(unsafeHtml, whiteList, sanitizeFn) {\n  if...

- Added a new feature gate `CelValidatingAdmissionExtensibility` to enable expression validation for Admission Control. ([#112792](https://github.com/kubernetes/kubernetes/pull/112792), [@cici37](https://github.com/cici37)) [SIG API Machinery]

- Added ports autocompletion for kubectl port-foward command. ([#124683](https://github.com/kubernetes/kubernetes/pull/124683), [@TessaIO](https://github.com/TessaIO)) [SIG CLI]
- Added support for CEL(Common Expression Language) expressions and `additionalProperties` to be used under nested quantifiers in CRD schemas. ([#124381](https://github.com/kubernetes/kubernetes/pull/124381), [@alexzielenski](https://github.com/alexzielenski)) [SIG API Machinery]

- CEL regex patterns in x-kubernetes-valiation rules are compiled when CRDs are created/updated if the pattern is provided as a string constant in the expression. Any regex compile errors are reported as a CRD create/update validation error. ([#108617](https://github.com/kubernetes/kubernetes/pull/108617), [@jpbetz](https://github.com/jpbetz))

translate($x, $y);\n}\n\n// Different radius each side\n@mixin border-radius-sides($top-left, $top-right, $bottom-left, $bottom-right) {\n  border-radius: $top-left $top-right $bottom-left $bottom-right;\n}\n\n@mixin calc($property, $expression) {\n  #{$property}: calc(#{$expression});\n}\n\n@mixin rotate($value) {\n  transform: rotate($value);\n}\n\n@mixin animation($animation) {\n  animation: $animation;\n}\n\n// Gradient background\n@mixin gradient($color: #f5f5f5, $start: #eee, $stop: $white) {\n  background-color:...