When you vein mine with auto-pickup enabled, it will stop once you get a new stack of whatever item, also happens when you try to vein mine a block that you have none of in your inventory(it will not trigger until you have atleast one of it)
UPDATE: It seems to only happen when you mine with an open hand
When you vein mine with auto-pickup enabled, it will stop once you get a new stack of whatever item, also happens when you try to vein mine a block that you have none of in your inventory(it will not trigger until you have atleast one of it)
UPDATE: It seems to only happen when you mine with an open hand