In any case, hadly 'Galaxy shaking'
It's 20 times heavier than the sun. It's hardly going to "shake a galaxy" when it goes. It'll be a typical type 2 burnout. Shining at several times the brightness of the full moon for maybe a week or two.
Type 2s blow off their surface layers when they go, and it is those surface layers that absorb the radiation from the explosion and produce the visible light. You, me, the air you breathe and everything in your imediate vicinity - all of this matter was createdd during a process just such as this, when some unknown star, or stars, exploded long in the past. Type 2s are the creators of worlds, not their destroyers.
Technically, no supernova could ever directly cause a mass extinction, anyway. Even a Gamma ray burst from a 1a would only blow off the planet's ozone layer on the exposed hemisphere: it would be your own star that then slowly irradiated all the life on the affected half of the planet during the days that followed. If you happened to have the good fortune to be on the shadow side from the burst, you'd probably retain enough ozone above you to survive until the ozone across the afflicted side had replenished itself.
No, sorry: the Brazilians are right. It's the greedy blue-eyed white bastards that will probably be the death of us, not some distant star.