This indicates that the address being analyzed incorporates content that is revealed upon the execution of JavaScript, meaning this content is not included within the primary HTML response of the page.
Why is this important?
Processing webpages is demanding on resources, and is considerably more time-consuming than just fetching the initial HTML content.
In its indexing process, Google employs a dual-phase strategy: initially, it examines the HTML response, followed by page rendering and a secondary examination of the rendered HTML. The index is then refined depending on the findings from the rendered content.
As such, it's possible for webpages to initially be indexed based on the initial HTML response, with a subsequent, indefinite period before the second analysis of the rendered content occurs.
Even though Google is adept at rendering pages to identify content created client-side, embedding critical content directly in the HTML response can be beneficial. Offering a glimpse of the primary text allows Google to ascertain relevance prior to the rendering phase.
This is particularly crucial for webpages with rapidly changing content, as you risk Google indexing an outdated version of the page.
What does the Optimization check?
This Optimization will activate for any internal address that features content generated through JavaScript within the designated content zone, as algorithmically determined by Loud Interactive.
Examples that trigger this Optimization
The Optimization is triggered by any URL exhibiting extra content in the rendered HTML not found in the response HTML.
For instance, if the initial HTML response appears as:
<!doctype html><html lang="en"><head> ...</head><body> <p>Initial content in the body</p></body></html>
And the fully rendered HTML after JavaScript processing is as follows:
<!doctype html><html lang="en"><head> ...</head><body> <p>Initial content in the body</p> <p>Additional content loaded by JavaScript</p> ...</body></html>
How do you resolve this issue?
According to Google guidelines, using JavaScript to load content is acceptable since Google will render and index every page that can be indexed, subsequently updating the index with the rendered content.
Nonetheless, that doesn't mean it's the most efficient practice from an optimization viewpoint, and this should be assessed for each specific website.
It's worth analyzing the extent to which JavaScript adds content. For augmenting a page with secondary details like product lists, JavaScript isn't typically problematic. But if the core narrative of the page depends on JavaScript, you're missing vital relevance signals until the page is rendered.
Comparing the site's approach with leading competitors can also provide insights into the use of JavaScript for content elements.