Loking at the uncraftable nbt-empty minecraft:potion tooltip causes a client crash:

java.lang.NullPointerException: Rendering screen
	at gloridifice.watersource.common.recipe.ThirstNBTRecipe.conform(ThirstNBTRecipe.java:20) ~[watersource:1.1.24b2-beta-1.16.5] {re:classloading}
	at gloridifice.watersource.common.recipe.ThirstItemRecipe.getRecipeFromItem(ThirstItemRecipe.java:103) ~[watersource:1.1.24b2-beta-1.16.5] {re:classloading}
	at gloridifice.watersource.client.event.tooltip.WaterLevelTooltip.onRenderTooltipEvent(WaterLevelTooltip.java:60) ~[watersource:1.1.24b2-beta-1.16.5] {re:classloading}
	at net.minecraftforge.eventbus.ASMEventHandler_42_WaterLevelTooltip_onRenderTooltipEvent_PostText.invoke(.dynamic) ~[?:?] {}
	at net.minecraftforge.eventbus.ASMEventHandler.invoke(ASMEventHandler.java:85) ~[eventbus-4.0.0.jar:?] {}
	at net.minecraftforge.eventbus.EventBus$$Lambda$2595/0x0000000000000000.invoke(Unknown Source) ~[?:?] {}

This happens with only watersource installed. But when without others mods this would happen only if someone uses /give xxxx minecraft:potion and then they look at that item tooltip.

However with others mods installed, any mod that uses a non-specific-nbt item "minecraft:potion" for a general recipe (example: druidcraft elderflower drink), this would make this same crash happen when looking at the potion through the recipe in JEI. Although in that case the client doesn't crash completely when looking at the item on JEI recipe section, but the errors still fires offs and the players hands disappear in-game. Also, having it accessible through JEI, makes booking marking that item possible through survival, and if you look into it then, in the bookmarked section, the client crashes completely the same way if the item was in the player inventory.