I have a question about template-ish parameters in a WPT. e.g., github.com/web-platform-tests/wpt/b…frame-options/multiple.sub.html#L76

it's setting an iframe's src to i.src = "http://{{domains[www]}}:{{ports[http][0]}}/x-frame-options/support/xfo.py?value=SAMEORIGIN&value2=SAMEORIGIN";

how is that expected to work?!

The server treats .sub. files as templates and replaces things in {{ }} with some runtime parameters

ok, thanks jgraham :)