HAND SANITIZER
We've seen news articles and reports that hand sanitizer left in your vehicle are prone to "spontaneously igniting". While hand sanitizers are flammable if they contain alcohol, the risk of them igniting due to extreme temperatures is highly unlikely. Guidance from the NFPA (National Fire Protection Association) says that temperatures in your vehicle will need to be in excess of 700°F for alcohol-based hand sanitizer to ignite. Exposure from from the sun during peak heating to your vehicle can produce temperatures in the 200°F range.
If the hand sanitizer is exposed to flame or prolonged sparks it's certainly possible for it to ignite but being that hand sanitizer has been such a hot commodity (excuse the pun), you're more likely to have it stolen from your vehicle than to have it ignite from the heat alone. You still do need to use caution when using alcohol-based hand sanitizers. Read the labels and don't use near an open flame. Store it in a glove box or center console so the sunlight and heat doesn't change the composition of the sanitizer.
Stay safe. Stay well.