Kiljoy healthbar visual bug after player dies

[jazzbloonist]

After a player dies when fighting kiljoy (solo), he is supposed to reset his health.
But very often his healthbar is not reset at all, being where i left him off after dying to mobs and other bosses or him, despite his health reseting, visually seeing him heal with that green effect. And when i respawn to fight him, his healthbar can get to beyond 0% and is not dead yet. Its a visual bug and only seldomly it resets to full hp on the healthbar.
Mostly i see this in elite maus map, not too sure about other maps. And im not sure if when a full party dies, the visual bug still happens.

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