Max Health Fixer is an unofficial backport of Darkhax's Max Health Fix.
This mod fixes an old bug in Minecraft that causes the "Max Health" attribute to be ignored when a player joins the game. This bug will cause players with a health value greater than the default limit of 20 to be reset back down to 20 when they join the game. For example, if the player is wearing a helmet that gives them +10 max health and they leave the game while having 25 health their health will be reset back to 20 when they rejoin the game.
ATTENTION:
You DEFINITELY CAN add the mod to your modpack.
I encourage you to ask for ports on other versions(Forge 1.6.4 ~ Latest, (Legacy)Fabric ALL, Rift).