How to get an outline effect on text in SVG?

Yes it can ;-)

I tried to realize that with Inkscape and then edited the source of the svg-File. Just don't fill it and use a stroke with color and width to draw it. I got that:

<text x="100" y="100" id="text2383" xml:space="preserve" style="font-size:56px;font-style:normal;font-weight:normal;fill:none;fill-opacity:1;stroke:#000000;stroke-width:1px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1;font-family:Bitstream Vera Sans">
<tspan x="100" y="100" id="tspan2385">D</tspan></text>

The interesting part is in the "style" attribute.

"fill:none;fill-opacity:1;stroke:#000000;stroke-width:1px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1;"

paint-order: stroke; worked wonders for me in this D3 chart I'm working on.

My final css:

.name-text {
    font-size:  18px;
    paint-order: stroke;
    stroke: #000000;
    stroke-width: 1px;
    stroke-linecap: butt;
    stroke-linejoin: miter;
    font-weight: 800;
}

My source (scroll down just a bit): https://svgwg.org/svg2-draft/painting.html#PaintOrderProperty