@pandaeyes and anyone else having this problem: install chrome extension.
For myself, lately whenever I engage in installing a chrome extension at the chrome store I am redirected to the main download page for Google Chrome. Yeah, not cool.
As has brought to my attention, http://crxextractor.com/ provides the work around. http://crxextractor.com/ contains a drop-in box wherein you paste the url of the extension you want in Opera. Then click "OK" you will or will not then see a specific crx file to paste into the "file box" provided to the left of the page.
Personally, I did not need to deploy developer tools to get the fix. All I had to do was to proceed to my extensions page where the new plug-in/extension was in a disabled state or accepted. Simply click "ok" and you have your new extension.
Weird s%^* to say the least.
Peace Out