Yes, can you believe that it is gorgeous out right now but in few hours rain is coming and tomorrow it might snow? That is what you get for being in New England!
Check that the sensor lenses are clean. Move a sensor each way (up and down and side to side) until the light goes out. Then set it back to the center of the area where the light stays on. Do this first with the transmitter then with the receiver.
I cleaned the sensors with the eyecare cleaner. I am very glad that this turned out to be easy but at least I did learn something about the safety mechanism.
I cleaned the sensors using eyeglass cleaner and microfiber. It is possible that the sensor is on the way out and I should probably order a spare just in case. I do not remember what would have caused the alignment to go off this time of the year as there is no bike or anything in that area. Getting more dirt and getting weaker over the years could explain the behavior. The aftermarket sensor kit runs about $25 from Amazon with few days of shipping. The only trouble with that approach is that I will promptly forget where I would have stashed it when the actual time comes to replace it!
Was it a bolt-on installation? Decades ago with my brother's help, we installed garage door opener from scratch in our townhouse. It was lot of work. I am assuming replacing an existing one with somewhat similar type should NOT be that much pain.