The variable m_isunderwater was removed and replaced by m_MirrorTimerFlags (and kinda by m_MirrorTimerFlagsLast) in the new map format commit: https://github.com/mangos/mangos/commit/485cb0cd34d47b68b098574060ce48379e6608e0
diff --git a/src/game/Player.h b/src/game/Player.h
index 836baf2..6fc9d58 100644
--- a/src/game/Player.h
+++ b/src/game/Player.h
@@ -68,7 +68,7 @@ enum SpellModType
SPELLMOD_PCT = 108 // SPELL_AURA_ADD_PCT_MODIFIER
};
-// 2^n values, Player::m_isunderwater is a bitmask. These are mangos internal values, they are never send to any client
+// 2^n internal values, they are never sent to the client
enum PlayerUnderwaterState
{
UNDERWATER_NONE = 0x00,