Can we have DBM not react when your max health changes from say a high level fortitude.
It is treating it like a loss of health, it even says I'm in combat when I'm not. It was a drive by 50 giving my 20 a big fort buff

the combat alert uses the actual combat api, in fact i designed that specifically for haredcore cause often times player didn't know they were in combat with things like a roach or an off screen mob pull so alerting in combat can literally save a life. but if it says you're in combat then you are in combat cause it is using PLAYER_REGEN_DISABLED to detect it. it's possible you were put into social combat as well by player buffing you who was in combat.

the health alert threshold only fires in two situations
you're AFK flagged (at any percent)
you're below 35%

if you have a habit of running around with afk flag on, that would lead to a VERY annoying experience. the intent behind that is again many hardcore deaths happen cause a user has tabbed out and doesn't see their character is being attacked or drowning. To improve this experience you use this feature by doing /afk any time you tab out as an added layer of protection. but when you are in game never use AFK flag.

all of these options can be disabled in DBM btw.