greasemonkey new relic unwrapper

restore_freeze_new_relic_wrapped_fns.js

(function (window) {
    const m = new Map(Object.entries({
        'window': new Map(Object.entries({
            'clearTimeout': new Map(Object.entries({
                'NREUM.o': 'CT',
            })),
            'setInterval': null,
            'requestAnimationFrame': null,
            'webkitRequestAnimationFrame': null,
            'Event': new Map(Object.entries({
                'NREUM.o': 'EV',
            })),
            'MutationObserver': new Map(Object.entries({
                'NREUM.o': 'MO',
            })),
            'Promise': new Map(Object.entries({
                'NREUM.o': 'PR',
                'prototype': new Map(Object.entries({
                    'then': null,
                    'catch': null,
                })),
            })),
            'Request': new Map(Object.entries({
                'NREUM.o': 'REQ',
            })),
            'setTimeout': new Map(Object.entries({
                'NREUM.o': 'ST',
            })),
            'XMLHttpRequest': new Map(Object.entries({
                'NREUM.o': 'XHR',
                'prototype': new Map(Object.entries({
                    'open': null,
                    'send': null,
                })),
            })),
            'History': new Map(Object.entries({
                'prototype': new Map(Object.entries({
                    'pushState': null,
                    'replaceState': null,
                })),
            })),
            'EventTarget': new Map(Object.entries({
                'prototype': new Map(Object.entries({
                    'addEventListener': null,
                    'removeEventListener': null,
                })),
            })),
            'Node': new Map(Object.entries({
                'prototype': new Map(Object.entries({
                    'appendChild': null,
                    'insertBefore': null,
                    'replaceChild': null,
                })),
            })),
        })),
    }));
    const new_relic_original = (typeof window.NREUM === 'object' && typeof window.NREUM.o === 'object') ? window.NREUM.o : null;
    const handle_map = function handle_map(scope, map) {
        for (const [k, v] of map.entries()) {
            if (k === 'NREUM.o') {
                continue;
            }
            if (v instanceof Map) {
                // constructor
                if (v.has('NREUM.o') && new_relic_original !== null) {
                    const key = v.get('NREUM.o');
                    const original = new_relic_original[key];
                    // console.log('restore native NREUM.o.%s: "%s" %o %o', key, k, scope[k], original);
                    Object.defineProperty(scope, k, {writable: false, configurable: false, value: original});
                }
                const target_scope = scope[k];
                handle_map(target_scope, v);
            } else {
                const fn = scope[k];
                if ('nr@original' in fn) {
                    // function
                    const original = fn['nr@original'];
                    // console.log('restore native nr@original: "%s" %o %o', k, scope[k], original);
                    Object.defineProperty(scope, k, {writable: false, configurable: false, value: original});
                } else if (fn.toString().includes('[native code]')) {
                    // non wrapped
                    // console.log('freeze native; "%s" %o', k, fn);
                    Object.defineProperty(scope, k, {writable: false, configurable: false});
                }
            }
        }
    };
    handle_map(window, m);
}(unsafeWindow));