When you try to add the extension to Chrome on your PC, you get a box asking if you're sure you want to install it, and tells you what privileges you are giving the extension:
It can read and modify all your data on the websites you visit
It can access your tabs and browsing activity
Then it says "Make sure that these privileges make sense for what you think the extension needs to do. If they do not, click cancel."
I don't see why it needs all of that just to send me a copy of my tablet's notifications.