Add the new, simplified Recaptcha2 ("I am not a robot"-checkbox) to your register and edit-forms. Based on the recaptcha-plugin by Adrian Schlegel. This plugin is not very actively maintained and is available for adoption.
reCAPTCHA provides a CAPTCHA with text from scanned books and images. This new version of recaptcha protects your registration form and edit forms from spammers, while posing a minimal hurdle for humans. For more information see http://www.google.com/recaptcha.
To use the reCAPTCHA service you need a Google account and create an API key at https://www.google.com/recaptcha/admin
- Plugins are generally asked to supply some usage facts, like what to do to get the plugin working. The user shouldn't have to download the plugin and examine the configuration or go to github and examine the code.
- The plugin has also been updated recently. Many users want to know dokuwiki version compatiblity. It's a simple thing to add it to the header at the same time that you are updating the plugin version date.