[Feature Request] Render custom SVG as background

[terenc3]

It would be nice to configure a SVG image as preview background. I have create a SVG with guidlines and padding which i use for designing icons. Currently i add it temporarily to the image to check if i'm inside the correct dimensions but it would be nice to have a configuration which i can set per project.

<svg viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg" fill="none">
    <g stroke="#2e2e32" stroke-width=".05">
        <path d="M0 0l24 24M0 24L24 0" />
    </g>
    <g stroke-linecap="square" stroke="red" opacity=".2">
        <path d="M.5.5h23M.5.5v23M.5 23.5h23m0-23v23" />
    </g>
    <g stroke-linejoin="round" stroke="green" stroke-width=".2" opacity=".2">
        <path d="M3 3h18v18H3z" />
        <circle r="10" cy="12" cx="12" />
    </g>
</svg>