For one, there was no explosion as it seems. Drone hit the building and what it seems from a video, just hit the ground after. No explosions - no casualties. Probably also no explosives on board. Maybe that was just surveillance/scout drone of some sorts. Who knows.

And also, what Ukranians do in Tuapse is also questionable. Ukranians basically bombed an oil storage and refineries in Tuapse that raised an environmental crisis in that area of the Black Sea. It is not a "Chernobyl" there, but just being at the area may raise long term health issues and of course god knows how long it will take to clean up oil spillages. There are casualties. But these are the side effect of what Ukranians targeted opposed to a "mistake coordinates" or whatever bullshit Russia would claim after bombing civilian areas.

Very questionable stuff indeed, but that is expected when you invade your neighbor country. After all, one is attacking while the other is defending. Moral of the story - make love, not war.