This mod adds the mechanic of adding time if you drink/splash the same potion.

For example: You take a 3 minute Night Vision potion and then take another 8 minute potion.
 - Vanilla: 8 minutes.
 - With Time Stacker: 11 minutes

Default time stack limit is 16 minutes. You can configure it in the config. If you don't want to stack a minecraft/mod effect you can do it adding the effect to the blacklist in the config.

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