That's not how you open a can of surströmming, nor how you eat it.

To open a can of Surströmming,  go outside, and fill a pail about two thirds with very cold water.  Immerse the Surströmming can in the water, fully under.  Did I emphasize that this is done outside?  Do it outside. Plunge your hands in, seize the can, and open it with a can opener while fully under.  Never, ever open it in the house, or inside anywhere, ever.   There you have it.

Pro tip: fermentation continues vigorously after canning.  When you pierce the can with the can opener, it releases a tremendous pressure build up, spraying the contents on everything.  If this happens, you will never get the smell out of your clothes.  If it gets in your eye, your eyeball will instantly liquify. Hence, the pail of water.

Second pro tip: Use the polluted water from the pail to kill weeds, varmints or neighborhood kids.

To eat Surströmming, cut it into little pieces and put them on a cracker with egg or cheese.  Little pieces.  Do this outside.   It is really not too bad that way.  Never eat it like these folk, right out of the can and inside.