Remove background, padding, border from breadcrumb container

scss/_variables.scss

@@ -1245,15 +1245,15 @@ $figure-caption-color:              $gray-600 !default;
 // Breadcrumbs
 
 $breadcrumb-font-size:              null !default;
-$breadcrumb-padding-y:              $spacer / 2 !default;
-$breadcrumb-padding-x:              $spacer !default;
+$breadcrumb-padding-y:              0 !default;
+$breadcrumb-padding-x:              0 !default;
 $breadcrumb-item-padding-x:         .5rem !default;
 $breadcrumb-margin-bottom:          1rem !default;
-$breadcrumb-bg:                     $gray-200 !default;
+$breadcrumb-bg:                     null !default;
 $breadcrumb-divider-color:          $gray-600 !default;
 $breadcrumb-active-color:           $gray-600 !default;
 $breadcrumb-divider:                quote("/") !default;
-$breadcrumb-border-radius:          $border-radius !default;
+$breadcrumb-border-radius:          null !default;
 
 // Carousel
 

site/content/docs/5.0/migration.md

@@ -43,6 +43,12 @@ toc: true
 - File inputs now use the `.form-control` class and don't require JavaScript, additional HTML, or additional classes. [See #31955](https://github.com/twbs/bootstrap/pull/31955).
 - Added `cursor:pointer` to `.form-control-color` color inputs.
 
+### Components
+
+#### Breadcrumbs
+
+- Set the default padding to `0`, and the background color and border to `null`, for the `.breadcrumb` styles. These can still be overridden using the `$breadcrumb-padding-x`, `$breadcrumb-padding-y`, `$breadcrumb-bg`, and `$breadcrumb-border-radius` variables.
+
 ### Utilities
 
 - **Text utilities:**