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Headline Testing troubleshooting

Valid vs. invalid HTML structure

To ensure accurate testing and tracking, Parse.ly’s Headline Testing requires a specific HTML structure. The system identifies the control headline using an anchor (<a>) tag that must follow a strict format.

Requirements for a valid HTML structure

  • The control headline must be included within the anchor tag’s content.
  • The anchor tag may contain multiple child elements, but at least one child must contain only the control headline text.
  • The control headline must not appear outside the anchor.

Valid example

<a href="/example-article">
  <h2>This is the control headline</h2>
</a>

In this case, the anchor tag contains one child element, and that element holds only the control headline. This structure is valid and supported.

Invalid examples

Example 1: Additional text

<a href="/example-article">
  <h2>Read more: This is the control headline</h2>
</a>

This is invalid because the tag containing the control headline contains additional text. The system cannot reliably extract the control headline.

Example 2: Headline outside the anchor

<div class="caption">
  <div class="category">Tips</div>
  <h2 class="title">How to Optimize Headlines with Testing</h2>
</div>
<a href="/article/headline-testing-101" title="How to Optimize Headlines with Testing"></a>

This is invalid because the control headline is placed outside the anchor. Although the anchor includes a title attribute, this is not sufficient for headline testing. The system requires the actual headline text to appear inside the anchor’s content.

Headlines are not being replaced

Possible issue: The control headline is being selected as the variant.

Solution: Check if the anchor has the vipexp-swapped-element class. If it does, the system is working as expected.
Possible issue: The script is being executed after the first contentful paint.

Solution: Try loading the script synchronously or enabling flicker control.
Possible issue: Mismatch in the URL or control text.

Solution: Ensure the anchor’s href attribute includes the canonical URL path. Additionally, the anchor must contain either:

1. The exact headline text with no extra text (though it may have child elements), or
2. At least one child element that exclusively contains the exact headline text.

Unable to see the ‘Create Test,’ ‘Start Test,’ or ‘End Test’ buttons

Possible issue: You do not have the necessary permissions to create or end tests.

Solution: By default, admins have the permission to manage headline tests. If you are not an admin, you can request the Manage Headline Test permission from an admin.

Last updated: June 16, 2025