Schematic illustration of a slice through the disk plane (only one side is shown due to symmetry). The black hole is shown as the circle on the left. The gray area represents the optically thick and geometrically thin disk where most of the accreting mass is located. The warm corona that covers the disk, in which the magnetic energy is released as radiation, is marked in orange. Magnetic and radiative energy flux are represented by blue and red arrows, respectively. The part of the corona that might collapse as a result of thermal instability is shown in magenta. The inner optically thin and geometrically thick hot flow that we did not consider is drawn in yellow for completion.