Sometimes water condensation (moisture, mist, bubbles, etc) will suddenly appear in one or both headlights on a vehicle. This is usually not caused by a crack. It is actually normal. Modern headlights are designed with vents in the back to allow air ventilation, which can sometimes allow moisture to enter the headlight. That moisture can condense if the headlight gets hot and fills with warm humid air and then the vehicle suddenly moves to a spot with cold air. Eliminating the moisture is easy, does not require special tools, and should not require you to remove your headlight, bumper, or any other such shenanigans. All you need for my technique is a vacuum cleaner, some tubing, some duck tape, and a hair dryer. And if you like the Fahren LED "bulbs" I brag about in this video, you can buy your own at Amazon.com using the link below. Just make sure you select the correct bulbs for your vehicle! (Mine are for a 2013 Dodge Grand Caravan R/T, a.k.a. "The Man Van.")
https://amzn.to/3DynFA3