Add LoginCookieCleaner

README.md

@@ -61,6 +61,9 @@ A common baseline of repeated functions, filters and actions used across our Wor
 - **Admin Separators**
   Admin Separators have been moved to their own library: [wp-admin-separators](https://github.com/ideasonpurpose/wp-admin-separators)
 
+- **Remove Stale Login Cookies**
+  Repeatedly spinning up local dev environments often bloats **localhost** cookies with stale `wordpress_logged_in` entries. Once these accumulate, the local server will eventually fail with a bad request and the error message *"Your browser sent a request that this server could not understand. Size of a request header field exceeds server limit."* The cookie can be removed using the browser's dev tools, if the error is recognized -- but it often isn't. Instead, wp-theme-init removes stale login cookies from the `wp_login` hook, preventing the issue. This only runs on development environments when WP_DEBUG is set.
+
 - **Media**
   Several media related features will be enabled:
 

src/ThemeInit.php

@@ -81,6 +81,12 @@ public function __construct($options = [])
          */
         new ThemeInit\Admin\LastLogin();
 
+
+        /**
+         * Clear stale wordpress_logged_in cookies
+         */
+        New ThemeInit\Admin\LoginCookieCleaner();
+
         /**
          * Add Metabox Reset buttons to Admin User Profiles
          */

src/ThemeInit/Admin/LoginCookieCleaner.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace IdeasOnPurpose\ThemeInit\Admin;
+
+class LoginCookieCleaner
+{
+    public $WP_DEBUG;
+
+    public function __construct()
+    {
+        // bridge WP_DEBUG for testing
+        $this->WP_DEBUG = defined('WP_DEBUG') && WP_DEBUG;
+
+        add_action('wp_login', [$this, 'remove']);
+    }
+
+    public function remove()
+    {
+        if (!$this->WP_DEBUG) {
+            return;
+        }
+
+        $stale_cookies = 0;
+        foreach ($_COOKIE as $key => $value) {
+            if (strpos($key, 'wordpress_logged_in') !== false) {
+                unset($_COOKIE[$key]);
+                setcookie($key, '', -1, '/');
+                $stale_cookies++;
+            }
+        }
+
+        if ($stale_cookies > 0) {
+            $msg = sprintf(
+                'IdeasOnPurpose\\wp-theme-init removed %d invalid `wordpress_logged_in` cookie%s',
+                $stale_cookies,
+                $stale_cookies == 1 ? '' : 's'
+            );
+            error_log($msg);
+        }
+    }
+}