Detect LazySizes
LazySizes is a JavaScript library used to delay the loading of images (iframes, scripts, etc) until they come into view.
Detection looks at javascript globals across 2 fingerprint rules among the site's public responses.
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Websites using LazySizes
Loading website list…
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Signal classes
PluginView evaluates public page signals in these classes when identifying LazySizes. Individual fingerprint rule bodies are proprietary and are not published.
- JavaScript globals
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Example public indicators for LazySizes
Illustrative indicators derived from public catalog metadata for LazySizes. A live scan may match additional proprietary rules beyond these examples.
- lazySizes
- lazySizesConfig
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What a detection means
- Establishes
- One or more public signals on the scanned page matched a known LazySizes signature (2 rules) at the time of the scan.
- Does not establish
- A sitewide install of LazySizes, an active vendor contract, exclusive use, or that LazySizes is still in place today.
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How to check a site for LazySizes
- 1. Enter the website URL in the scan form — homepage, pricing, checkout, or login pages usually expose the strongest LazySizes signals.
- 2. PluginView reads only public responses (javascript globals) and scores them against the LazySizes signature set (2 rules).
- 3. Review the confidence score and text explanation for LazySizes on the results page.
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FAQ: detecting LazySizes
- Can PluginView detect LazySizes without logging in?
- Yes. PluginView only reads publicly accessible responses when checking for LazySizes — typically javascript globals. It does not bypass authentication or paywalls.
- What category is LazySizes?
- LazySizes is classified under JavaScript libraries, Performance in the PluginView directory.
- How many fingerprint rules cover LazySizes?
- This reference currently tracks 2 fingerprint rules across javascript globals. Individual rule bodies are proprietary and are not published.
- What public signals suggest a site uses LazySizes?
- Illustrative public indicators for LazySizes include lazySizes; lazySizesConfig. A live scan may match additional proprietary rules beyond these examples.
