START switch broken

My START switch is stuck in the “ON” position. The knob is broke and we were gently using a pair of needlenose pliers to cut on and off. My concern is if it is safe to leave the Dryer energized with the START switch constantly ON. The cycle switch has 3 OFF positions but I have concerns about the closed START switch. How difficult is it to replace the START switch? Thanks in advance for your response!

Sorry, this is an electric dryer.