I use PDF-XChange viewer under WINE. The save a new copy thing in Okular is just too awkward, I really need the annotations to travel with me across viewers and platforms. PDF XChange seems to be crashing more here than it was under Linux Mint Cinnamon (I’m new to OpenSUSE). But even with frequent crashes, at least it does what I need.
Too bad there isn’t a native Linux app of the same caliber.