player: runtime-src is honoured for srcdoc only - an src embed always fetches the runtime from jsDelivr

Author: srinvasmishraCreated Sep 16, 2026Updated Sep 16, 2026

Summary

<hyperframes-player> accepts a runtime-src attribute, and validates it carefully (http/https, same-origin or loopback). But it is only ever read on the srcdoc path:

javascript

function H(r, e) { return qe(It(e, ...), Pt(r)); }   // srcdoc  -> honours runtime-src (Pt)
function F(r, e) { return Lt(e, ...); }              // src     -> URL params only

The probe that injects the runtime into an src iframe uses the module constant instead, with no access to the host element:

javascript

var k = "https://cdn.jsdelivr.net/npm/@hyperframes/[email protected]/dist/hyperframe.runtime.iife.js";
_injectRuntime() {
  this._runtimeInjected = true;
  const t = doc.createElement("script");
  t.src = k;                       // <- always the CDN
  (doc.head || doc.documentElement).appendChild(t);
}

So an src embed cannot be given a local runtime. On an offline or air-gapped machine, or behind a script-src 'self' CSP, the injection silently fails (it is inside a bare try {} catch {}), __hf never appears, and the element eventually emits error: "Composition timeline not found after 8s".

Reproduction

comp-nested.html — a [data-composition-src] child makes the probe inject immediately:

xml

<!doctype html><html><head><meta charset="utf-8"></head><body>
  <div id="root" data-composition-id="main" data-width="1080" data-height="1920">
    <div data-composition-src="child.html" data-start="0" data-duration="5"></div>
  </div>
</body></html>

host.html, served over http from the same origin as a local copy of the runtime:

xml

<script src="https://cdn.jsdelivr.net/npm/@hyperframes/[email protected]/dist/hyperframes-player.global.js"></script>
<hyperframes-player src="comp-nested.html" runtime-src="/local-runtime.js"
                    width="1080" height="1920"></hyperframes-player>

Actual

The network panel shows

GET https://cdn.jsdelivr.net/npm/@hyperframes/[email protected]/dist/hyperframe.runtime.iife.js  200

and no request for /local-runtime.js. runtime-src passes the element's own validation and is still ignored.

Expected

src and srcdoc resolve the runtime the same way: runtime-src when it is set and valid, the jsDelivr default otherwise. Concretely, pass the resolved URL into the probe (it is already computed by Pt(host)) instead of closing over the module constant, so an embed can serve its own pinned copy.

Two smaller things that would help either way:

the injected <script> has no onerror, so a blocked or 404 runtime is indistinguishable from a slow one — the element just times out after 8 s with a message about the timeline;
documenting runtime-src as srcdoc-only would at least make the current behaviour discoverable.

Environment

@hyperframes/player 0.8.41, Chromium 141, Linux

Why it matters

A local review tool that embeds staged projects has to reach a CDN for every composition it opens, or pre-inject the runtime into the served HTML itself (which is what we now do) — even though the exact matching runtime is already sitting in node_modules/hyperframes/dist/.

Source: heygen-com/hyperframes

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