With the most recent version (2.4-b03d), the tooltip showing the insulation level of an armor piece no longer appears. Not sure if this is something in the config, but I checked some settings and wasn't able to figure out if it was an issue just on my end or not.

Image of the tooltip for the Goat Fur Cap:

Interesting. I don't get this issue in my testing, so it might be an issue relating to your configs. I would try deleting the item.toml config file and see if it regenerates correctly.

Regenerating config helped for me

Perfect. Must have been a one-off issue, then. Thanks for following up.