Blocked: All third-party storage access requests

Firefox:

CookieBlockedForeign=Request to access cookies or storage on "X" was blocked because we are blocking all third-party storage access requests and content blocking is enabled.

A request to access cookies or storage was blocked because it came from a third-party (a different origin) and content blocking is enabled.

The permission can be changed or removed by:

• Going to Preferences > Content Blocking and either
• adding an exception with the Manage Exceptions… button
• choosing the Custom Content Blocking and unchecking the Cookies checkbox

If the resource that is being blocked doesn't need authentication, you can fix the warning message by adding a crossorigin="anonymous" attribute to the relevant element.

• Content blocking on support.mozilla.org
• The crossorigin attribute