We have a snippet of code that was provided by an optimization platform company we use that provides a real-time personalization to our website.

The user will fill out a form (Gravity Forms) and then be sent to one of our WordPress Thank You pages.

This code will be added to the Thank You page, but needs to be updated to capture the user’s email address once the Gravity Form has been completed:

<img src="//dasd65f4ds3e25u.cloudfront.net/pc/p5w6g1jy/?e=[customer's email address]" id="__tms_pc" height="1" width="1" />

Would you be able to help me replace the "customer’s email address" text with the appropriate code that will be able to capture each user’s email address when they fill out the form?

Is there a PHP string of code that could be used to replace the "customer’s email address" text?
I have not been able to find a concrete answer while doing some research for this.