- Sign up with a new username to a Wikimedia site.
- Edit an article and add an external link.
- Try saving.
After entering an edit summary and pressing the button in the dialog, the dialog remains and the CAPTCHA is shown in its bottom. At least on my machine, I need to scroll down in the dialog to actually see the CAPTCHA. I saw new users puzzled over this - they thought that they already pressed the save button and couldn't understand why is the dialog still there.