Custom lingering potions & tipped arrows show incorrect duration

The bug

When you give a player a lingering potion or tipped arrow with custom effects, it shows the duration incorrectly; for example, if we use this command:

/give @p minecraft:tipped_arrow{custom_potion_effects:[{id:"minecraft:blindness",amplifier:0,duration:60}]} 

It doesn't show 3 seconds at all. However if you were to do

/give @p minecraft:tipped_arrow{custom_potion_effects:[{id:"minecraft:blindness",amplifier:0,duration:600}]}

It shows 3 seconds

Video: https://youtu.be/c7bxWXvj-1o

Code analysis

Code analysis by Marcono1234 can be found in this comment.