>If you check the filename of the windows installer you download from the frontpage the name is FileZilla_Version_Sponsored-setup.exe

Damn...that reminds me of the old days of sneaky checkboxes hidden in installers, usually actually hidden, that would be pre-checked confirming your consent to whatever ad/spyware to be installed alongside whatever you wanted to install.

I remember that shit being everywhere for a few years. Got tricked by them once or twice and had a hell of a time cleaning things up after.