Opera is a series of web browsers developed by Opera Software AS
Safari is Apple's web browser, the default browser on macOS and iOS.
"Works in google-chrome firefox a bit weirdish blur effect on hover opera ends look smaller safari ends look smaller"
from question "Creating a Radial Menu in CSS"
"Incidentally the scrolling on the windows version of safari is fine albeit a little slower than ie opera and firefox"
from question "Extremely slow CSS3 box-shadows in Chrome"