/**
     * Get the value for the key 'app.extension.names'. <br>
     * The value is, e.g.  <br>
     * comment: Extension names for application customization.
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getAppExtensionNames();

    /**
     * Get the value for the key 'app.extension.names' as {@link Integer}. <br>
     * The value is, e.g.  <br>

- ACTION REQUIRED : In CoreDNS v1.7.0, [metrics names have been changed](https://github.com/coredns/coredns/blob/master/notes/coredns-1.7.0.md#metric-changes) which will be backward incompatible with existing reporting formulas that use the old metrics' names. Adjust your formulas to the new names before upgrading. 
  
  Kubeadm now includes CoreDNS version v1.7.0. Some of the major changes include:

* Fix OpenAPI/JSON Schema generation for two functions with the same name (in different modules) with the same composite bodies.
    * Composite bodies' IDs are now based on path, not only on route name, as the auto-generated name uses the function names, that can be duplicated in different modules.
    * The same new ID generation applies to response models.

xl: 1200px, xxl: 1400px))\n//    md\n//    >> breakpoint-next(sm, $breakpoint-names: (xs sm md lg xl xxl))\n//    md\n@function breakpoint-next($name, $breakpoints: $grid-breakpoints, $breakpoint-names: map-keys($breakpoints)) {\n  $n: index($breakpoint-names, $name);\n  @if not $n {\n    @error \"breakpoint `#{$name}` not found in `#{$breakpoints}`\";\n  }\n  @return if($n < length($breakpoint-names), nth($breakpoint-names, $n + 1), null);\n}\n\n// Minimum breakpoint width. Null for the smallest (first)...

breakpoint-next(sm, (xs: 0, sm: 576px, md: 768px, lg: 992px, xl: 1200px))\n//    md\n//    >> breakpoint-next(sm, $breakpoint-names: (xs sm md lg xl))\n//    md\n@function breakpoint-next($name, $breakpoints: $grid-breakpoints, $breakpoint-names: map-keys($breakpoints)) {\n  $n: index($breakpoint-names, $name);\n  @return if($n != null and $n < length($breakpoint-names), nth($breakpoint-names, $n + 1), null);\n}\n\n// Minimum breakpoint width. Null for the smallest (first) breakpoint.\n//\n//    >> breakpoint-min(sm,...