VRTs - Visual Regression Tests

With visual regression testing, you can detect errors and unwanted changes on your website by comparing a previous state of the website with a more recent one. For example, errors in the frontend can be caused by plugin updates and changes. For small websites, you may be able to find them right away, but for complex websites, it becomes difficult. A tool can help by taking pictures of pages and posts to detect visual changes and inform you automatically.

Tests can be done manually, pixel-by-pixel, DOM-based or AI-based. In all cases, you compare an earlier website state with a newer one. Our Visual Regression Tests Plugin takes periodical screenshots and compares them on a split screen.

You can do visual testing either manually or with automated tools. Checking your website for errors manually is time-consuming and less accurate. Automated tests may find errors that are minimal and irrelevant. But the chance of finding critical errors is much higher with a tool. As soon as you discover an error, you'll receive a warning so that you can fix the problem as soon as possible.

Screenshots and comparisons are performed on an external server and sent to your WordPress website. Only required meta data is stored in your database.

If our external screenshot service cannot access your WordPress installation directly, test status updates and sending emails will be handled by the WP-Cron system. In order to be notified by the plugin about new alerts, please make sure that your WordPress instance can send emails and that the WordPress cron system is set up correctly. The default configuration of the WordPress cron system does not work reliably if you cache your site heavily, do not have frequent visitors or do not use wp-admin regularly. In this case, you should hook the WP-Cron into the system task scheduler, or use an external cron job scheduling service.

Yes, cookie banners are not an issue. Before taking a snapshot, the tool can automatically trigger the Accept button to hide the banner. This option can be configured with CSS selectors in the plugin settings.

The VRTs plugin primarily supports WordPress pages and posts. Automated visual testing of pages with dynamically changing content can lead to false positives. However, you can test such pages by following these steps:

• Create a new blank page or post in WordPress.
• Set up a redirect from this page to your desired URL.
• Configure a test for this page. The screenshotter will follow the redirect.

If your firewall is blocking our screenshot service, whitelist our IP address to resolve this: 49.13.14.240. For Cloudflare, follow these steps:

1. Log in to your Cloudflare account.
2. Navigate to Security → WAF.
3. Click on Tools.
4. In the IP Access Rules box, enter 49.13.14.240.
5. Select Allow from the action dropdown.
6. Add “VRTs” as the note.
7. Click Add.