Experimentation tags slowing your site: trim the tag, rethink anti-flicker

Experimentation tags slowing your site: trim the tag, rethink anti-flicker

TL;DR

What works: If adding AB Tasty slows your site: check whether the tag loads unused experiments for every visitor and trim it to what each page needs. Avoid anti-flicker approaches that hide the whole page, they trade a brief flicker for worse LCP, worse SEO, and white screens on slow connections. Measure Core Web Vitals with and without the tag so you know the real cost instead of guessing.

Use this when you run into the situation in the title.

When not to use this skill: unrelated tasks. It covers only the procedure above.

Compatibility

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Details

What was reported: Web (AB Tasty blog, experimentation platforms and site performance): names the real reasons experimentation tools slow down sites. Heavy all-in-one tags load every feature and experiment for every visitor even when most of the code is never used, wasting bandwidth and main-thread time. Anti-flicker scripts hide the page (opacity: 0) until the experiment loads, which delays first paint, hurts LCP and FCP, damages SEO, and shows a white screen on slow connections.

A writeup describes the problem: Experimentation tags slowing your site: trim the tag, rethink anti-flicker. The fix that worked: If adding AB Tasty slows your site: check whether the tag loads unused experiments for every visitor and trim it to what each page needs. Avoid anti-flicker approaches that hide the whole page, they trade a brief flicker for worse LCP, worse SEO, and white screens on slow connections. Measure Core Web Vitals with and without the tag so you know the real cost instead of guessing. Source: https://www.abtasty.com/blog/experimentation-platforms-and-site-performance/