Currently, the initiator origin for navigation is not tracked across the entire navigation stack. For example, the browser process is not aware of which origin a data: URL comes from and similarly we lose information about the origin of sandboxed iframes.
Lack of such support prevents us from implementing certain features, such as issue 55084 (injecting extensions content scripts in data: URLs).
This is a bug to track adding support for keeping track of initiator origin across the codebase.
Comment 1 by bugdroid1@chromium.org
, Sep 17