I tried this command:
/give @p potion{display:{Name:'{"text":"Mystical Potion"}'},CustomPotionEffects:[{Id:8,Amplifier:2b,Duration:300,ShowParticles:0b},{Id:14,Amplifier:1b,Duration:200,ShowParticles:0b},{Id:28,Amplifier:1b,Duration:300,ShowParticles:0b}]} 1
This potion should give the player invisibility, jump boost and slow falling, but when I use that command I'll get a uncraftable potion with no effects. This command worked in 1.20.1, but as they updated the version to 1.20.2 recently, this command doesn't seem to work anymore. Aswell as my other commands that include custom potion effects.
So because it worked in the last version and doesn't get an error in this version, I was wondering if they maybe changed the syntax of this command, like instead of using square brackets you have to use normal brackets or something like that?