Filter URL Field by Watcher

Hi everyone,
How can I filter URL Field before the email action?

Example:

URL: https://discuss.elastic.co/

URL_FILTER: https://discuss[.]elastic[.]co/

I'm not sure what you are referring too, but if URL is a field obtained from the input query, you can use a scripted field using painless to process the field before it gets passed to the email action. In the email action simply use the scripted field instead of the actual one. https://www.elastic.co/guide/en/kibana/current/scripted-fields.html