Same issue for me and my partner in co-op. The game seemingly randomly crashes. No clear triggers it can vary from farm work, mines, walking around town, etc.
We have also been running in to issues where my partners "floor in the mines" will break. No enemies spawn and no drops can be collected if he's able to find the staircase it'll fix on the next level.
Also we had an issue where the volcano mines loaded two separate "floors" for me and my partner when we went there together. I was unable to leave, had to use a warp totem back home.
Also our cat disappeared, completely gone from our animal list.
Lastly we have experienced a bug where our barn animals will come outside to eat grass, they walk up to the grass and then just stand there. No truffle drops or anything they wouldn't move around just stand. We have to restart the game when this happens no other workaround.
I have played Stardew Valley on and off for many years on PC, Xbox, Playstation, and Switch and I have never across these issues before so I'm assuming they are specific to 1.6 on console.
Hoping the team is aware of the Xbox issues because it is ALMOST unplayable in this state. Though I would be lying if I didn't say we have tried to just push through by replaying the days, losing out on resources, etc.