I upgraded Opera on one of my windows10 drives and syched and installed onto a new little notebook I picked up and then went to a new Fedora 23 (Gnome) install on another computer. To my surprise, the install from the Opera Software AS [NO] https website turned out to be a very old version of Opera, OR possibly I had that sitting on my drive from previous session...it would not even take my long email address for synching...which is what led me to check the version...it was like 2:12.16!!!
So I went back and got the 38 rpm and the install failed as the /etc folder was occupied.
I was a afraid I got a redirect to a spoof site and maybe had some kind of trojan on board. That fear was exacerbated when the opera version did not show under "installed" in my gnome software manager...
Fortunately, sudo dnf uninstall opera went like a charm. I was a little nervous as various dependency files were deleting but as it turned out they were either replace or unessential. (gstreamer-tools/plugin base etc)
I am still scratching my head...as it turned out Opera 38 synched perfectly and instantly