I am running Safari 8.0.4 on OS X 10.10.2
I think when I installed filezilla there was also a malicious browser extension installed in Safari. Here is what the extension preferences panel looks like:
This extension seems to make everything go to yahoo. My home page and search engine is now changed to Yahoo. I can't get it back to what it was before. I also can't install any other browser extensions in Safari. Any help is appreciated :-)