imgfixer/data_src.js

// ==UserScript==
// @name     data-src Image Fixer
// @version  1
// @grant    none
// @match    https://www.atlasobscura.com/*
// @match    https://hayleyisaghost.co.uk/*
// @match    https://threadreaderapp.com/*
// ==/UserScript==

function fixImages() {
  for (let img of document.getElementsByTagName('img')) {
    let imgUrl = img.getAttribute('data-src');
    if (imgUrl) {
    	img.setAttribute('src', imgUrl);
      img.style.height = 'auto';
    }
  }
}

fixImages();