https://chrome.google.com/webstore/detail/ckibcdccnfeookdmba...
If you want to recommend an alternative then why not point to google's own: https://chrome.google.com/webstore/detail/cpngackimfmofbokmj...
Screengrab for Firefox has been doing this for a long time now. It also allows you to select a region to capture with your mouse.
https://addons.mozilla.org/en-US/firefox/addon/screengrab/