Imagine this: You activate GTM’s Preview and Debug mode, eagerly refresh your webpage, and as it loads, a perplexing “Form Submit” event flashes across the Preview console, despite no form submission taking place. Even more baffling, some pages don’t even feature a form!
What’s behind this?
The answer lies with the Facebook Pixel.
A Brief Overview
Not all websites encounter this phenomenon, but it’s a familiar sight for many.
Before the “Window Loaded” event makes its appearance, a “Form Submit” event emerges out of thin air, even on formless pages.
This anomaly arises under two conditions: the presence of Facebook Pixel on your page and at least one active GTM Form Submission trigger.
These “ghost” form submissions, disconnected from your site’s actual forms, signal a deeper issue.
The Root Cause
Facebook Pixel adopts a unique approach to data transmission, utilizing form submissions as a cross-browser-safe method, according to insights from Simo Ahava in the GTM Community.
This process involves the creation, submission, and deletion of a form with your data, irrespective of actual form presence on the page. GTM’s Form Submission trigger merely reflects these submissions, distinguishing them through specific Data Layer parameters.
Addressing the Form Submit Phantom Submissions
Regarding the false Form Submit events—triggered by Facebook Pixel’s unconventional data handling method—there’s a limitation to direct action. These events will persist in your preview and debug modes as long as a Form Submission trigger is active. However, to prevent inadvertent tag firing by these events, it’s advisable to refine your trigger conditions.
I would recommend firing the Facebook Pixel at the window load and not at the page level. This will ensure it does not slow down the site or other, more important tags.
