The CombatProt plugin reserves bars to fill out a raid, this protect against random players leaving the group/raids, with random players then joining during combat.

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• Enable plugin - When a plugin exists in your addons folder and is loaded, it can still be shutdown from within HealBot options.
• Global profile - Use current settings on all characters, uncheck to use on the Player only.
• Use Combat Protection in groups - Use when in groups.
• Use Combat Protection in raids - Use when in raids.
• Use Crash Protection - If a disconnect happens during combat, crash protection protects frames when connecting in combat.
• Macro name - Crash Protection uses a macro to track the current state, this label shows the name used.