What is a TODO add-on from TODO company, unverified publisher and why is my homepage trying to run it?

Question

My Yahoo homepage I guess is trying to run this. Should I let it run? Why is the publisher unverified?

Answer 1

This seems to have been asked on YA several times, and none of the askers appears to have gotten a good answer, though the consensus seems to be that it's a benign but unnecessary add-on to Internet Explorer.  

The odd thing is that I've been using Yahoo a lot and have never gotten this.   That makes me think that it might be some kind of spyware that's associated with some other site you visit.   Another weird thing is that I can't find out anything about it other than from YA questions and answers.