Did you bother to read the article? This is exactly what it talks about.
Please don't insinuate that someone hasn't read an article. "Did you even read the article? It mentions that" can be shortened to "The article mentions that."
It actually does directly mention microwaves:
> The Russian security services were also known to flood the U.S. embassy in Moscow with electromagnetic radiation. They would beam concentrated microwaves and electronic pulses at the Embassy in an attempt to eavesdrop on U.S. typewriters and conversations.