Having a sensor means you can also trust your popcorn button. Technology Connections did a great video about this, if your microwave uses the sensor properly, the popcorn button starts by clearing the chamber of moisture by running the fan and the sensor. Then it turns on the microwave element, and when the bag inflates enough to open there’s a sudden puff of moisture into the chamber. The oven detects this, and uses a lookup to determine how much longer to run the microwave element based on how long it ran the element before sensing moisture, which accounts for different sizes and weights. You’ll hear a beep and see a few seconds left on the display.

This is nearly perfect in my experience. Every now and then the popcorn is very slightly burnt, but being able to just press a button and walk away is awesome.

Definitely watch the video, I didn’t realize mine had this feature until an earlier video of his about popcorn buttons (this one, specifically).