Always at your service!
Surströmming is not available in Germany to my knowledge, I had it once in Norway, the trick is open the can in a bucket of water -under the surface- to avoid the putrid smelling gases! It tasted ...strange and fishy, but not that awful.
Good tip about the Surströmming...but I might just leave it in the bucket...or crab pot.
Oddly here, the local hoarders are not buying pickled or preserve vegetables: those large jars of Polish ill pickles, onions, sauerkraut (Aldi special) & girardiniera for example.