### External credential providers

Kubernetes client [credential plugins](https://kubernetes.io/docs/reference/access-authn-authz/authentication/#client-go-credential-plugins) have been in beta since 1.11, a few eons ago. With the release of Kubernetes 1.22, this feature set graduates to stable. The GA feature set includes improved support for plugins that provide interactive login flows.

    display: block;\n    width: $custom-control-indicator-size;\n    height: $custom-control-indicator-size;\n    content: \"\";\n    background: 50% / #{$custom-control-indicator-bg-size} no-repeat;\n  }\n}\n\n\n// Checkboxes\n//\n// Tweak just a few things for checkboxes.\n\n.custom-checkbox {\n  .custom-control-label::before {\n    @include border-radius($custom-checkbox-indicator-border-radius);\n  }\n\n  .custom-control-input:checked ~ .custom-control-label {\n    &::after {\n      background-image:...