Hey Tom, I'm really sorry you went through so much trouble! I have had
this issue documented on the installation page
(https://chrome.google.com/extensions/detail/jeoacafpbcihiomhlakheieifhpjdfeo),
but I know these issues are hard to spot (and correlate back to
Disconnect).
Disconnect's popup bubble will have a "Help" link soon, but I'm not
sure how much that'll, er, help. If you've got other suggestions,
please let me know!
P.S. You should be able to temporarily deactivate Yahoo blocking, log
into Flickr, and then reactivate Yahoo blocking and use Flickr as
normal.