NO! It wasn't logging anything! The only thing it was doing was proxying clicks on search results through Ecosia's analytics servers instead of Google's.
Anyone who still has the extension installed can view the source code by looking in their /%USER_FOLDER%/<PATH_TO_CHROME>/Extensions/kkelicaakdanhinjdeammmilcgefonfh The extension is also available at http://ionut-botizan.net/window-resizer/ both as a .zip and .crx file.
"No, that's bundled adware. If I wanted to give you malware, I would have added a keylogger which you wouldn't have ever discovered (ask around; it's technically possible). So stop whining already, uninstall the extension and move on with your life!" http://productforums.google.com/d/msg/chrome/mlAD1ygc0v0/FL6...
(Also, he's now posting on the linked thread. 7 minutes ago last reply.)
seems to imply that he was not logging keystrokes, which conflicts directly with the first post in that thread:
> they are tracking all data and keystrokes. checked with wireshark.
It'd be nice to have a copy so that we can find out for ourselves.