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http csp directive

Content-Security-Policy: fenced-frame-src directive

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The HTTP Content-Security-Policy (CSP) fenced-frame-src directive specifies valid sources for nested browsing contexts loaded into <fencedframe> elements.

CSP version 1
Directive type [Fetch directive](https://developer.mozilla.org/en-US/docs/Glossary/Fetch%20directive)
Fallback If this directive is absent, the user agent will look for the `frame-src` directive (which falls back to the `child-src` directive).

Syntax

Content-Security-Policy: fenced-frame-src <source-expression-list>;
  • <source-expression-list>
    • : A space-separated list of source expression values. Resources of this type may be loaded if they match any of the given source expressions. For this directive, the following source expression values are applicable:

Examples

Violation cases

Given this CSP header:

Content-Security-Policy: fenced-frame-src https://example.com/

The following sources will not load in a fenced frame:

  • https://not-example.com/ (domain doesn’t match)
  • https://example.org/ (TLD doesn’t match)

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also