When analyzing Snapshots of pageviews, you may notice they are returning high volume of
None values in your results.
This is because pageview snapshots fire as soon as Heap loads, which is right around the DOMContentLoaded event. Often, elements will not render on the page until after the pageview event has fired, so the Snapshot will not be able to capture those elements.
We recommend implementing Snapshots on a click, submit, or change event that occurs after the pageview if it is intended to capture an element that is not available on page load.