Deprecate `invisible()` mixin (#28066)

scss/mixins/_visibility.scss

@@ -4,4 +4,5 @@
 
 @mixin invisible($visibility) {
   visibility: $visibility !important;
+  @include deprecate("`invisible()`", "v4.3.0", "v5");
 }

scss/utilities/_visibility.scss

+// stylelint-disable declaration-no-important
+
 //
 // Visibility utilities
 //
 
 .visible {
-  @include invisible(visible);
+  visibility: visible !important;
 }
 
 .invisible {
-  @include invisible(hidden);
+  visibility: hidden !important;
 }

site/docs/4.2/utilities/visibility.md

@@ -17,13 +17,14 @@ Apply `.visible` or `.invisible` as needed.
 {% highlight scss %}
 // Class
 .visible {
-  visibility: visible;
+  visibility: visible !important;
 }
 .invisible {
-  visibility: hidden;
+  visibility: hidden !important;
 }
 
 // Usage as a mixin
+// Warning: The `invisible()` mixin has been deprecated as of v4.3.0. It will be removed entirely in v5.
 .element {
   @include invisible(visible);
 }