When you spur of the moment decide to turn your gaming pc into a proxmox machine and then miss gaming so you end up down a rabbit hole of iommu groups to pass your Gpu through to a steam os VM to wrestle with Linux virtual display drivers so you can use sunshine to cast your games to your laptop

It eventually worked but you can quickly end up in a niche hell hole with little to no coherent documentation.

Trash guides is a gateway drug

Your individual shower habits might be predictable enough to if than your way to it with existing sensors.

If you track current draw on your boiler / water heater that would indicate a draw on hot water during time when you typically shower. You can add other checks for it to pass if you find too many false positives.

If you’re as glued to your phone as every one else alive atm a simple rfid / wireless charger or something you set your phone on when you strip for the shower triggering the event will likely be the most straight forward approach unless you bring your phone in the shower lol I’m occasionally guilty if the podcast is good enough 😅