• Summary / Title: Enabling auto-explore for a water unit or a land unit once embarking is unlocked results in suicide.
• Description: Units on auto-explore in my game would not avoid deep water, resulting in their inevitable deaths if I failed to disable auto-exploration before I unlocked high seas navigation.
• Steps to Reproduce: Use auto-explore with early ships or with land units after embarking is unlocked.
• Reproducibility: 5/5
• Expected Behavior: Units should not commit suicide. I would expect units that can't safety travel through deep water to either avoid it entirely, know to not end movements there, or know to never spend more than one turn in deep water.

I've noticed this too and agree -- coastal only ships shouldn't wander out into open water and stay there more than one turn.