Recently I saw in Halacha that it is inappropriate to have the sermon right before Kaddish of Musaf as it is considered a Hefsek. Yet many Shuls do just that and have the sermon right before Kaddish ...
Not sure where it came from, but many people tend to say Yisbarach after the Amen Yehei Shmei Rabbah verse. Where did this come from? Is this correct?
Can you ever say Kaddish without a Minyan?