An idea to stop accidiential dropping.

[Mateusz_Zboj]

Any time you hold an item in hand for longer than 30 sec you should have that item put back into any possible slot by automatical means. (Unless it is watersking/flask and the character is swimming)
An option should be added into menu to create warning messages when you want to drop items into water or drop items that disappear after dropping. (perhaps it would be nice if we were able to customize it somehow)

[painhertz]

You're reaching......

[Mateusz_Zboj]

Welp I think at least modders could do something like this.

[Kriegwolf]

YOU DON'T SWIM AND DRINK.
Actually, mods could go here and close this.

[jesi]

Don't you get it? The OP had just dropped his waterskin into a river. Et voila, an Idea.

[iceheart]

The firat thing I will do if there is an option to this is to turn it off. A prompt to confirm a manual drop is going to be far too annoying to keep around.

[Arcanist]

I like the idea, I've dropped a few undroppable curios in the past.

Also there should be a function to keep some items in your inventory when you shift + scroll, I'm sick of losing my flasks in cupboards/large chests.

[FictionRyu]

I've dropped a few undroppable curios in the past.

With Enders client it has the option to 'lock' your mentory window so that you don't accidentaly drop any curios.

[Mateusz_Zboj]

Don't you get it? The OP had just dropped his waterskin into a river. Et voila, an Idea.

Read properly.

[DDDsDD999]

There's been lock inventory item mods since W4, not sure if any are public though, could probablly dig around and find some.