I think I've found a workaround.
By adding a viewBox
, Firefox decides to render it properly. See line 8:
<div>
<svg id="svg_viewport"
width="800" height="800"
style="background-color: pink"
>
<svg id="o_1"
x="10" y="10" width="200" height="200"
viewBox="0 0 200 200"
>
<image href="https://www.1kfa.com/table/img/image.png"
height="200" width="200"></image>
</svg>
<svg id="o_2"
x="0" y="100" width="100" height="100"
>
<rect id="r_2"
width="100" height="100"
fill="green"
></rect>
</svg>
</svg>
</div>
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…