Max stack problem

[Boomboomcreeper]

i opened doc lua_api and i changed Stack max form 99 to 64 but nothing

[Topywo]

To change the stack_max, you need to put that line under the registering in the init.lua. Here I have an example of a changed stack_max for the dirt in the default mod:

minetest.register_node("default:dirt", {
description = "Dirt",
tiles = {"default_dirt.png"},
is_ground_content = true,
stack_max = 64,
groups = {crumbly=3},
sounds = default.node_sound_dirt_defaults(),
})

Edit: more info:
1. When you changed the init.lua, you need to exit to the menu and start again to let it take effect
2. When you had for example 99 dirt, made the change to 64 in the init.lua and then restarted your game, the dirt stack is still 99. But when you halve it and try to put it together again, the max wil be 64.