Since Russia is going to send only 2 people crew to the ISS for a while, I wonder how will they adapt the spacecraft.
Do they remove the 3rd seat ? Can they put extra cargo on theses flights ?
MS-04 has been launched with 3 seats. The 3rd seat will be needed when MS-04 returns to Earth with 3 crewmembers (the third is Expedition 51 Commander Peggy Whitson).
For launch, the empty seat on Soyuz MS-04 will be filled by a cargo container.