Onely which has analyzed a sample of popular e-commerce and news websites has analyzed JS of the website & has some amazing data on how Google indexing of these pages along with unindexed JavaScript content on these pages is impacting.
Some findings are
Nike – 22% of the indexed pages have unindexed JavaScript content
Sephora – 55% of the indexed pages have unindexed JavaScript content
H&M – 65% of the indexed pages have unindexed JavaScript content
A good study guide for developers, digital marketers, e-comm on how to develop pages for improved indexing & CX
Via – https://www.onely.com/blog/javascript-more-popular-than-you-think/
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