The inkscape extension link is to a empty page: https://inkscape.org/~MarioVoigt/%E2%98%85imagetracerjs-for-...
"Vectorize" generator in Boxy SVG also uses imagetracerjs under the hood, you can check the online demo here: https://boxy-svg.com/#demo-tracing
I think Inkscape still uses Potrace internally, which is produces a bit better results.