casalemedia.com
So, Thunderbird has quit downloading my emails from yahoo.com and given me a popup window from https://r.casalemedia.com telling me to sign in using my yahoo account. I ran a sophos antivirus scan of my system and it came back clean. I have gone to "add or remove programs" to see if something got loaded in there and can't find anything. What is this and how do I get Thunderbird working right again?