lazyload policy grants the ability for a document to control whether
assets are loaded lazily, ie. only when the user scrolls the docuement such that the
asset is within the visible area of the viewport.
If the policy is enabled, or not specified, the document has full control over
lazy-loading, using the lazyload
<iframe> tags. If the
policy is disabled, the user agent will lazy-load all assets regardless
of the presence or value of any
lazyload attribute on the element itself.
How to apply this policy
Send the following HTTP header to control the
lazyload policy, and disallow
it on all origins:
Feature-Policy: lazyload 'none'
Does it work?
Currently Firefox, and Chromium based browsers, such as Google Chrome, Samsung Internet,
and Opera, are the only user-agents to support Feature Policy. The minimum version that
correctly recognises the
lazyload policy is: