When you double tap Shadow Word: Death via a target dying with Death and Madness active, the second Shadow Word: Death cast isn't being counted towards Death and Madness incoming insanity/ticks/duration.

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Reported by dota in Warcraft Priests Discord.

[11:06 AM] dota: Low priority but I've notice incoming insanity not updating if you activate D&M a second time while it's active @Twintop
[11:07 AM] dota: https://streamable.com/hla26m
[11:07 AM] dota: https://i.imgur.com/ExIFtpa.png