You can use https://overpass-turbo.eu/ instead.
This repository/tool has been deprecated, mainly because https://tools.wmflabs.org/query2map/ appears to be unmaintained (it appears to be broken for quite a while, at least).
qtm_gui was an interface for building URL's for OpenStreetMap's Query-to-map, built with HTML/JavaScript.
Browse the source prior to the deprecation if you wish.
A (broken, see above) demo available here .