- form-action 'self': injected markup cannot post a native form off-origin - frame-src 'none': no framed content; a sandboxed srcdoc preview is not fetched and still renders - header tests, README and admin-spa docs name the directives
- form-action 'self': injected markup cannot post a native form off-origin - frame-src 'none': no framed content; a sandboxed srcdoc preview is not fetched and still renders - header tests, README and admin-spa docs name the directives