JavaScript libraries; Performance
Who left Intersection Observer, and who still runs it
154 websites in the top 1M run Intersection Observer, observed directly from the rendered page in the July 2026 crawl.
28
stopped running it that month
2
of those are 11–500 employees
62
adopted it in the last year
Confirmed across two consecutive crawls, not a single month. Build the list →
Some companies running Intersection Observer
Every row in a full list carries the prospect's whole detected stack.
Not currently available as a list.
What else they run
jQuery 94%Google Analytics 79%Open Graph 79%jsDelivr 75%core-js 75%Google Font API 69%Cloudflare 66%PHP 59%Google Tag Manager 57%Facebook Pixel 47%
Share of a 154-domain sample of Intersection Observer users that also run each.