Something called "Funnelcake" just downloaded on my laptop? Was this from you?
I ask because Firefox always updated without interaction from me and all of a sudden, I start getting messages that were NOT from Firefox saying my browser was out of date, and the link did not name any connections I am familiar with. Today, I wasn't able to back out of the message like I was earlier in the week. Today, it downloaded and forced a reboot without my permission.
Sorry to hear that, I don't know what funnelcake is (in the software sense).
You could check the Windows Control Panel, Programs and Features, to see whether you can remove it there. You can click the header on the install date column to find the most recently installed programs.
certain firefox downloads get designated as funnelcake builds by mozilla for metrics gathering purposes... this should not related to pop-ups advertising false updates. can you provide a screenshot of such a popup?