The Chat trigger condition Visitor page URL has a lot of options and variations, and a freeform text box! What is the correct way to use this condition to get the results I want?
The Visitor page URL condition has various options on how you implement it.
You can use Equals if you want this trigger to act on chats initiated from an exact specific webpage URL. Make sure you include the full url in the text box, so that it matches the full URL of the webpage.
If instead you want this chat trigger to run on all pages that start with the same URL but may end differently, use the Contains option as shown in the dropdown below. For example, if you want the trigger to fire on the URLs "www.example.com/checkout/payment", "www.example.com/checkout/review" and "www.example.com/checkout/confirm" you can use Visitor page URL > Contains > www.example.com/checkout.
You could also use the Contains condition to include all URLs with a certain keyword. For example Visitor page URL > Contains > checkout. This would mean the trigger runs on any page that it is embedded on that has "checkout" in the URL. So it would run on "www.example.com/checkout" as well as "www.checkout.com" and "www.example.zendesk.com/hc/en-us/how-to-use-the-checkout-page" and more.
For more information on each of the trigger operators and how they work, see this article: Zendesk Chat triggers conditions and actions reference - Trigger operators.