osm-achavi.user.js

// ==UserScript==
// @name        Achavi-Link on OSM.org
// @namespace   de.schaeferban
// @include     https://openstreetmap.org/user/*/history*
// @include     https://www.openstreetmap.org/user/*/history*
// @include     http://openstreetmap.org/user/*/history*
// @include     http://www.openstreetmap.org/user/*/history*
// @include     https://openstreetmap.org/changeset/*
// @include     https://www.openstreetmap.org/changeset/*
// @include     http://openstreetmap.org/changeset/*
// @include     http://www.openstreetmap.org/changeset/*
// @version     1
// @grant       none
// ==/UserScript==
function getAchaviLink(changesetId) {
  var achaviLink = document.createElement('a');
  achaviLink.setAttribute('href', 'https://overpass-api.de/achavi?changeset=' + changesetId);
  achaviLink.setAttribute('target', '_blank');
  achaviLink.setAttribute('class', 'button');
  achaviLink.setAttribute('style', 'min-width:0;min-height:0;padding:.5em;margin:.25em;line-height:1');
  achaviLink.appendChild(document.createTextNode("Achavi"));
  return achaviLink;
}

window.onload = function() {
  console.log('Changeset list for user')
  var changesets = document.querySelectorAll('div.changesets ol li');
  for (var i = 0; i < changesets.length; i++) {
    if(changesets[i].getAttribute('id').match(/^changeset_[1-9][0-9]*/)) {
      changesets[i].appendChild(getAchaviLink(changesets[i].getAttribute('id').substring(10)));
    }
  }

  var browseSection = document.querySelector('div.browse-section');
  var changesetLink = document.querySelector('div.secondary-actions + div.secondary-actions a');
  if (browseSection !== null && changesetLink !== null) {
    console.log('Changeset details page');
    if (changesetLink.getAttribute('href').match(/^\/api\/0\.6\/changeset\/[1-9][0-9]*/)) {
      browseSection.appendChild(getAchaviLink(changesetLink.getAttribute('href').substring(19)));
    }
  }
}