当在 SVG 元素上指定了 xml:base 属性时，Mozilla Firefox 不理解 SVG 文档内 xlink:href 属性上的本地 IRI 引用。
相同的 SVG 文档在 Google Chrome 中显示良好。
尝试删除 xml:base 属性，Firefox 通过其本地 ID 找到该元素：
<?xml version="1.0" encoding="utf-8"?>
<svg version="1.1"
xml:base="http://samplehost.com"
xmlns:ev="http://www.w3.org/2001/xml-events"
xmlns:svg="http://www.w3.org/2000/svg"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns="http://www.w3.org/2000/svg"
viewBox="0 0 236.00000 148.00000"
height="148.00000"
width="236.00000"
>
<def>
<symbol id="86310c35-a7e1-47c0-90c8-b6f912d2cead" viewBox="0 0 113.39 70.87" enable-background="new 0 0 113.39 70.87">
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</def>
<use xlink:href="#86310c35-a7e1-47c0-90c8-b6f912d2cead" x="0" y="0"/>
</svg>