Replace Thumbnail URL

Replace Thumbnail URL WordPress plugin that rewrites attachment image URLs to use a custom domain (for example a CDN or public site URL) instead of the current site URL. Works as a standard plugin or as a must-use (mu) plugin. Requirements | Requirement | Version | |-------------|---------| | WordPress | 5.0 or higher | | PHP | 7.4 or higher | Features - Rewrites domains in attachment URLs (wpgetattachmenturl) - Rewrites sized image src values (wpgetattachmentimagesrc / related helpers) - Rewrites srcset URLs (wpcalculateimagesrcset) - Settings field under Settings → Media to set the custom media domain - Defaults to the current site URL (no rewrite) until you change it Installation Standard plugin 1. Copy the replace-thumbnail-url folder into wp-content/plugins/. 2. In Plugins, activate Replace Thumbnail URL. 3. Go to Settings → Media and set Custom media domain if needed. Must-use (mu) plugin Must-use plugins load automatically and cannot be deactivated from the admin UI. WordPress only autoloads PHP files directly in wp-content/mu-plugins/ (not in subfolders). Option A — single file 1. Copy replace-thumbnail-url.php into wp-content/mu-plugins/. 2. Done. T