I add my voice to the precedent ones. This is not only extreemly annoying to be cut in the midst of one's productivity, but also creepy, as I get the feeling Evernote is peeping and prying over my shoulder constantly : "Oh I can see you are opening a PDF... is it interesting ? lemme see..." By searching how to disable it, I came to this old thread. So, yes, I clear my cookie cache everyday. Please stop this or at least allow an opt out feature.