It’s now possible with the ContentSettings API,
and there is an extension named Quick Javascript Switcher that turns on/off javascript on the fly : https://github.com/maximelebreton/quick-javascript-switcher
QJS on the Chrome Webstore : https://chrome.google.com/webstore/detail/geddoclleiomckbhadiaipdggiiccfje
Enjoy !
seo : disable javascript chrome extension