This plugin saves a player's potion effects when they die so they can be given back when the player respawns. If the player is to leave the server while dead, they will get the effects back after re-joining and respawning. If the server shuts down while the player is dead (or offline while dead) then their effects will be lost.
Commands
/peff reload - Reloads the config file
/peff toggle - Toggles saving on/off
All commands require the permission persistenteffects.admin