docs: fix a few redirects (#31689)

* Fix GitHub's permanent redirects

* Fix a11yproject redirects

* Update postcss-loader repo URL to the current  one

6 files changed, 7 insertions, 7 deletions

diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index 75841c222e..34da5de091 100644
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -215,7 +215,7 @@ includes code changes) and under the terms of the
 [Adhere to the Code Guide.](https://codeguide.co/#css)
 
 - When feasible, default color palettes should comply with [WCAG color contrast guidelines](https://www.w3.org/TR/WCAG20/#visual-audio-contrast).
-- Except in rare cases, don't remove default `:focus` styles (via e.g. `outline: none;`) without providing alternative styles. See [this A11Y Project post](https://a11yproject.com/posts/never-remove-css-outlines/) for more details.
+- Except in rare cases, don't remove default `:focus` styles (via e.g. `outline: none;`) without providing alternative styles. See [this A11Y Project post](https://www.a11yproject.com/posts/2013-01-25-never-remove-css-outlines/) for more details.
 
 ### JS
 
diff --git a/README.md b/README.md
index d018bc2d02..b3caa9072a 100644
--- a/README.md
+++ b/README.md
@@ -68,8 +68,8 @@ Read the [Getting started page](https://v5.getbootstrap.com/docs/5.0/getting-sta
 [![peerDependencies Status](https://img.shields.io/david/peer/twbs/bootstrap)](https://david-dm.org/twbs/bootstrap?type=peer)
 [![devDependency Status](https://img.shields.io/david/dev/twbs/bootstrap)](https://david-dm.org/twbs/bootstrap?type=dev)
 [![Coverage Status](https://img.shields.io/coveralls/github/twbs/bootstrap/main)](https://coveralls.io/github/twbs/bootstrap?branch=main)
-[![CSS gzip size](https://img.badgesize.io/twbs/bootstrap/main/dist/css/bootstrap.min.css?compression=gzip&label=CSS%20gzip%20size)](https://github.com/twbs/bootstrap/tree/main/dist/css/bootstrap.min.css)
-[![JS gzip size](https://img.badgesize.io/twbs/bootstrap/main/dist/js/bootstrap.min.js?compression=gzip&label=JS%20gzip%20size)](https://github.com/twbs/bootstrap/tree/main/dist/js/bootstrap.min.js)
+[![CSS gzip size](https://img.badgesize.io/twbs/bootstrap/main/dist/css/bootstrap.min.css?compression=gzip&label=CSS%20gzip%20size)](https://github.com/twbs/bootstrap/blob/main/dist/css/bootstrap.min.css)
+[![JS gzip size](https://img.badgesize.io/twbs/bootstrap/main/dist/js/bootstrap.min.js?compression=gzip&label=JS%20gzip%20size)](https://github.com/twbs/bootstrap/blob/main/dist/js/bootstrap.min.js)
 [![BrowserStack Status](https://www.browserstack.com/automate/badge.svg?badge_key=SkxZcStBeExEdVJqQ2hWYnlWckpkNmNEY213SFp6WHFETWk2bGFuY3pCbz0tLXhqbHJsVlZhQnRBdEpod3NLSDMzaHc9PQ==--3d0b75245708616eb93113221beece33e680b229)](https://www.browserstack.com/automate/public-build/SkxZcStBeExEdVJqQ2hWYnlWckpkNmNEY213SFp6WHFETWk2bGFuY3pCbz0tLXhqbHJsVlZhQnRBdEpod3NLSDMzaHc9PQ==--3d0b75245708616eb93113221beece33e680b229)
 [![Backers on Open Collective](https://img.shields.io/opencollective/backers/bootstrap)](#backers)
 [![Sponsors on Open Collective](https://img.shields.io/opencollective/sponsors/bootstrap)](#sponsors)
diff --git a/scss/mixins/_visually-hidden.scss b/scss/mixins/_visually-hidden.scss
index 26edfe84be..d980696c80 100644
--- a/scss/mixins/_visually-hidden.scss
+++ b/scss/mixins/_visually-hidden.scss
@@ -2,7 +2,7 @@
 
 // Hide content visually while keeping it accessible to assistive technologies
 //
-// See: https://a11yproject.com/posts/how-to-hide-content/
+// See: https://www.a11yproject.com/posts/2013-01-11-how-to-hide-content/
 // See: https://hugogiraudel.com/2016/10/13/css-hide-and-seek/
 
 @mixin visually-hidden() {
diff --git a/site/content/docs/5.0/getting-started/accessibility.md b/site/content/docs/5.0/getting-started/accessibility.md
index 022efcc203..150c80d65c 100644
--- a/site/content/docs/5.0/getting-started/accessibility.md
+++ b/site/content/docs/5.0/getting-started/accessibility.md
@@ -50,7 +50,7 @@ Bootstrap includes support for the [`prefers-reduced-motion` media feature](http
 ## Additional resources
 
 - [Web Content Accessibility Guidelines (WCAG) 2.1](https://www.w3.org/TR/WCAG21/)
-- [The A11Y Project](https://a11yproject.com/)
+- [The A11Y Project](https://www.a11yproject.com/)
 - [MDN accessibility documentation](https://developer.mozilla.org/en-US/docs/Web/Accessibility)
 - [Tenon.io Accessibility Checker](https://tenon.io/)
 - [Color Contrast Analyser (CCA)](https://developer.paciellogroup.com/resources/contrastanalyser/)
diff --git a/site/content/docs/5.0/getting-started/webpack.md b/site/content/docs/5.0/getting-started/webpack.md
index 10e536bbf2..c67152f8d9 100644
--- a/site/content/docs/5.0/getting-started/webpack.md
+++ b/site/content/docs/5.0/getting-started/webpack.md
@@ -42,7 +42,7 @@ First, create your own `_custom.scss` and use it to override the [built-in custo
 @import "~bootstrap/scss/bootstrap";
 {{< /highlight >}}
 
-For Bootstrap to compile, make sure you install and use the required loaders: [sass-loader](https://github.com/webpack-contrib/sass-loader), [postcss-loader](https://github.com/postcss/postcss-loader) with [Autoprefixer](https://github.com/postcss/autoprefixer#webpack). With minimal setup, your webpack config should include this rule or similar:
+For Bootstrap to compile, make sure you install and use the required loaders: [sass-loader](https://github.com/webpack-contrib/sass-loader), [postcss-loader](https://github.com/webpack-contrib/postcss-loader) with [Autoprefixer](https://github.com/postcss/autoprefixer#webpack). With minimal setup, your webpack config should include this rule or similar:
 
 {{< highlight js >}}
 ...
diff --git a/site/layouts/_default/docs.html b/site/layouts/_default/docs.html
index 5d390a5f80..d54e2a9fde 100644
--- a/site/layouts/_default/docs.html
+++ b/site/layouts/_default/docs.html
@@ -17,7 +17,7 @@
       <main class="bd-main order-1">
         <div class="bd-intro pt-md-3 pl-lg-4">
           <div class="d-md-flex flex-md-row-reverse align-items-center justify-content-between">
-            <a class="btn btn-sm btn-bd-light mb-2 mb-md-0" href="{{ .Site.Params.repo }}/tree/main/site/content/{{ .Page.File.Path }}" title="View and edit this file on GitHub" target="_blank" rel="noopener">View on GitHub</a>
+            <a class="btn btn-sm btn-bd-light mb-2 mb-md-0" href="{{ .Site.Params.repo }}/blob/main/site/content/{{ .Page.File.Path }}" title="View and edit this file on GitHub" target="_blank" rel="noopener">View on GitHub</a>
             <h1 class="bd-title" id="content">{{ .Title | markdownify }}</h1>
           </div>
           <p class="bd-lead">{{ .Page.Params.Description | markdownify }}</p>