Potential UI or gameplay bug around heat capacity

https://medal.tv/games/marathon/clips/mg6dkY7aDG_ctAnPY?invite=cr-MSxlbk8sMzA5OTcwMjM&v=36

On steam, just moments before the timestamp of the video. I had this loadout and did not notice any gameplay impact of havving 0 heat cap, so I think its just a UI bug, but with two mods together, a shield and a head mod that did not remove any heat cap, I was netting -45 heat cap. Instead of what should be a -1 heat cap due to -5 from shield and +4 from the other implant.