为什么 Chrome 中的 SVG 中不显示表情符号?

Why is the emoji not displayed in the SVG in Chrome?

SVG 中的表情符号在 Safari 和 Firefox 中都能正确显示。在 Chrome 和 Opera 中它根本不显示。我需要做什么才能让表情符号也显示在 Chrome 和 Opera 中?

<svg id="SVGbgcolor1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="256" height="256" viewBox="0 0 144 144" alt="SVG Bitcoin Pictograph">
    <g>
        <text id="flag" x="0" y="136" font-family="courier" font-size="144"></text>
        <g id="SVGbgcolor2" transform="matrix(2.403433 0 0 2.403433 133.9157 -.2672786)" fill="#ffff11" stroke="black">
        <path d="m-29.67313 32.30631c-0.0078 3.964844-0.01563 7.929687-0.02344 11.89453 4.250716-0.05757 9.512582 0.672079 12.68164-2.011719 2.020462-1.485994 1.7925-8.830264-2.508482-9.337212-3.355145-0.489526-6.76593-0.500321-10.14972-0.5456z"></path>
        <path d="m-29.66532 15.95475 0.09375 9.896485c3.94585-0.118673 9.206302 0.331177 11.81609-1.285296 2.052885-1.630257 1.024997-8.44682-3.021329-8.344769-2.954353-0.25838-5.925276-0.251126-8.888509-0.26642z"></path>
        <path d="m-56.63264-1.090505-0.08727 63.0228 62.6767-0.05623-0.033283-62.95665zm22.46341 6.233736h7.091797v4.530687h4.558594l-0.147496-4.383191h7.132551l-0.05164 4.411386c5.97362 0.3102366 11.03635 8.194718 8.783373 13.20227-1.403588 2.992536-4.061669 5.443424-7.199219 6.509766 4.270871 0.752585 9.289582 2.353423 9.201172 8.21875 0.4854457 8.953997-3.897788 10.18234-10.63281 13.90966v4.358297h-7.089844v-4.379284h-4.554687v4.52678h-7.091797v-4.52678h-10.81445l-0.05977-5.75189c1.541302 0.125363 4.914709-0.106688 4.939639-2.629801-0.03614-7.277082 0.06346-18.24454-0.02479-25.51909-0.172768-2.90147-4.855077-2.632184-4.855077-2.632184v-5.314695h10.81445z"></path>
        </g>
    </g>
    <circle id="rounded1" cx="72" cy="72" r="72" stroke="black" stroke-width="2" fill="transparent"></circle>
    <rect x="0" y="0" width="144" height="144" stroke="#ffffff" fill="#ffffff" fill-opacity="0" stroke-opacity="0"></rect>
</svg>

解决了。需要将 font-size 更改为 71 或更少 (font-size="71")。似乎在 Chrome 55.0.2883.95 中更大的 font-size 不会导致任何渲染。虽然表情符号存在于代码中,但在使用 toDataURL 时可以看到。