web-page-monitor

Try it

Create a bookmarklet on your browser (and then try it where policies allows you to) using the following:

which comes from the following:

Install it

yarn add web-page-monitor

Use it

import 'web-page-monitor'

WebPageMonitor
    .showFPS(/* options */)
    .showMEM(/* options */)
    .showTAGS(/* options */)
    .showEVENTS(/* options */)
    .showLOAD(/* options */)
    .showNET(/* options */)
    .showVIEW()
    .render({where: document.body /* default is body */, collapsible: true /* default false */});

if You want to render elsewhere just pass {where: YourTargetNode} when calling render.

Available panels