One of the important issues that Sunnis believe is Omar was the caliph of the holy Prophet (peace be upon him and his ahl beit). In this hadiths from Sunnis book, it will be mentioned that Omar was worthless for this position and how he disrespected the Prophets (peace be upon him and his ahl beit) podium.
The point is Omar broke wind when he was on the podium, menbar.
Madaeni said: When Omar was on the podium, menbar, he broke wind, and then he said: o people! I was in dilemma between choosing fear from God or fear from you, and I chose fear from God. Therefore, know that I farted, so I am going to make Vozu, again. (Oyun ol- Akhbar, ibn Ghotaybe Dinvari, published by Al-Mesrye Maktab, v.1, chapter Tavazo ol aemash, p.267)