v5: Drop remaining deprecated mixins (#28461)

- Deletes mixin mentions from float docs
- Deletes mixin mention from visibility docs
- Deletes the image-replacement page for text-hide

site/content/docs/4.3/utilities/float.md

@@ -10,32 +10,12 @@ toc: true
 
 These utility classes float an element to the left or right, or disable floating, based on the current viewport size using the [CSS `float` property](https://developer.mozilla.org/en-US/docs/Web/CSS/float). `!important` is included to avoid specificity issues. These use the same viewport breakpoints as our grid system. Please be aware float utilities have no affect on flex items.
 
-## Classes
-
-Toggle a float with a class:
-
 {{< example >}}
 <div class="float-left">Float left on all viewport sizes</div><br>
 <div class="float-right">Float right on all viewport sizes</div><br>
 <div class="float-none">Don't float on all viewport sizes</div>
 {{< /example >}}
 
-## Mixins
-
-Or by Sass mixin:
-
-{{< highlight scss >}}
-.element {
-  @include float-left;
-}
-.another-element {
-  @include float-right;
-}
-.one-more {
-  @include float-none;
-}
-{{< /highlight >}}
-
 ## Responsive
 
 Responsive variations also exist for each `float` value.