This is slow, but it works, to find the text that's highlighted by a monaco editor

monaco-highlight-finder.js

// Paste this into JS to find an ACE editor in your browser window
// Based off of https://stackoverflow.com/questions/12102425/recursively-search-for-a-value-in-global-variables-and-its-properties/12103127#12103127
function isTarget(obj) {
    // return typeof obj == typeof value && obj == value
    if (obj && obj['getModel'] && obj.getModel() && obj.getModel().getValueInRange) {
      const highlight = obj.getModel().getValueInRange(obj.getSelection())
      if (highlight) {
        console.log('highlight', highlight);
        return true;
      }
    }
    return false;
}
function globalSearch(startObject, isTargetFunc) {
    var stack = [[startObject, '']];
    var searched = new Set();
    var found = false;

    var isArray = function (test) {
        return Object.prototype.toString.call(test) === '[object Array]';
    }

    while (stack.length) {
        var fromStack = stack.pop();
        var obj = fromStack[0];
        var address = fromStack[1];

        searched.add(obj);
        try {
            if (isTargetFunc(obj)) {
                var found = address;
                console.log(address);
                return obj.getModel().getValueInRange(obj.getSelection());
                // break;
            }
            if (typeof obj == "object") {
              // dive into the object
                if (isArray(obj)) {
                    var prefix = '[';
                    var postfix = ']';
                } else {
                    var prefix = '.';
                    var postfix = '';
                }
                for (key in obj) {
                    if ([
                      // comment out more of these to have a more thorough but redundant search
                      // '_rootLView',
                      // '_view', '_hostLView', '_cdRefInjectingView',
                      '_lView', '_declarationLView', '_lContainer', '_thenViewRef',
                      'next', 'prev', 'parent', '_parentOrParents',
                      'children', 'firstElementChild', 'lastElementChild', 'offsetParent', 'previousElementSibling', 'nextElementSibling', 'ownerDocument',
                      'styleSheets', 'parentNode', 'parentElement', 'childNodes', 'firstChild', 'nextSibling', 'previousSibling', 'lastChild',
                    ].includes(key)) {
                      continue;
                    }
                    if (prefix === '.' && !key[0].match(/[_a-z]/i)) {
                      prefix = '["';
                      postfix = '"]';
                    }
                    if (searched.has(obj[key])) {
                      continue;
                    }
                    stack.push([obj[key], address + prefix + key + postfix]);
                }
            }
        } catch (err) {
            // console.log("error at", address, err);
        }
    }
    // return found == '' ? true : found;
    return false;
}

globalSearch(window, isTarget);