In reply to Ed Sutherland.

@Ed - the extension should work on Chrome+Mac, a few suggestions:

1. Make sure that the extension is installed on your Google Drive account (the extension is installed per google account, not per browser). If you're not sure if it is installed or not, try logging in to your Drive account and then install the extension again while you're still logged in.

2. Make sure that you are right clicking a Google Document (not a spreadsheet or an uploaded file - uploaded files, even if they are word (*.doc) files, need to be converted to be Google Documents first).

3. If you are using the new Google Drive user interface, try switching back to the classic one by clicking on the settings button in your Drive account, and selecting "Leave the new Drive" from the menu.

Hope it helps