I have a phone with a thermal imager too!

I mostly use it to brag to people about how I have a phone with a thermal imager!

But here is a demonstration that glass will reflect a bit of thermal radiation, but is completely opaque to thermal behind it:

As long as you aren’t touching the glass, wherein the glass will conduct your thermal signature:

And then if you take the hand away, the signature remains on the glass for several minutes!

As a bonus, my phone also has a microscope, and I learned that my facial hair is sometimes triangular:

Used to have one of these too.

Just because nobody asked:

Check where the heat loss is occurring in your house.