Simple trick!
Edit any website in your browser here are some steps to do this!

1- Go to a website for example facebook.com,
2- Clear the address bar.
3- Copy the code below and paste it in your address bar

javascript:document.body.contentEditable='true';
document.designMode='on'; void 0

Make Sure that javascript: is exist at the beginning of the code
or Code will not work

enjoy!!!