[gpm]

Nuclear incidents, not really. There has been some mild spread of radioactive material near Chernobyl.

However there has been strategic use of them against Ukraine. Russia attacked and captured Zaporizhzhia and then used it as a base of operations on the front line that Ukraine couldn't attack back, because Ukraine is much less willing to risk a nuclear incident on their own territory than Russia is. Nuclear reactors strategically favour the invading army, because they care less about being careful.

It's also really not valid to say "the really bad thing didn't happen this time, so it's fine". Avoiding any meltdowns ever means even "that looked vaguely close to something bad happening" is something that must be avoided, and there have been several times in this war where it's looked more than vaguely close.