To load and embed the SVG file, I used the following markup:

<iframe src="signal.svg" onload="this.before((this.contentDocument.body || this.contentDocument).children[0]);this.remove()"></iframe>

Despite the fact that this markup starts out as an iframe, if you inspect the graphic above using developer tools, you’ll see the SVG markup for the icon, inlined right in the HTML DOM, with no iframe element to be found. This is because the code uses an iframe to load the file, and an onload event to inject the iframe’s content just before the iframe in the HTML, before deleting the iframe itself.

Loading and interactivity performance as experienced by real-world Chrome users across a diverse set of hardware and network conditions, powered by the Chrome User Experience Report.

Abstract Upstream HTTP/1.1 is inherently insecure and regularly exposes millions of websites to hostile takeover. Six years of attempted mitigations have hidden the issue, but failed to fix it. This p