[Question] Why is the war in Ukraine particularly dangerous for the world?

I have heard that since WW2 there have been ~140 armed conflicts in the world. Only few of them have been full-fledged wars, let alone big ones. However, as I don’t know almost anything about wars and the politics around them, I cannot really formulate why this war is particularly dangerous and prone to start WW3. This one is specially frightening for me because it is very close by—I’m European--, but this does not make it more prone to e.g. start WW3.

I have thought of few factors (location, countries involved /​ potentially involved, possession of nuclear weapons...) but the war in Ukraine does not seem to be too special in any of them. Is it maybe the combination of factors what it makes it particularly dangerous? As many may, like me, not be too versed in geopolitics/​geostrategy, I think it would be useful to compile a list of key factors setting this war aside from all the other wars the world has endured since WW2 and making it particularly dangerous for the whole world.