Can players activate reactions during the Combat Damage Step, or do they lack priority during this step?

Ruling: Players do not have priority during the Combat Damage Step, so no reactions or other discretionary actions can be activated. Any reactions must be activated before the Combat Damage Step begins.

Nuances:

• The Combat Damage Step is technically in a neutral open state, but players are "in between" states as the game engine processes combat damage
• The comprehensive rules could be clearer about explicitly removing priority during this step, as they primarily focus on when priority is granted rather than when it's taken away
• "Up to one player" having priority means 0 or 1 players can have priority at any given time