oh-my-zsh disable lib history.zsh

This question is old but anyway:

As you can use setopt for setting options, you can use unsetopt to unset them.

Just add

unsetopt share_history

after having sourced $ZSH/oh-my-zsh.sh

(and yes, it's really annoying ;) )

I mean, what is the RIGHT way. It is a lib not a plugin, if I edit the file I will not get updates for it.

The accepted answer is the easiest way, but it bears mentioning that oh-my-zsh lets you override any file or plugin you want by putting it in $ZSH_CUSTOM - even stuff in lib. If you want to do more than just unsetopt share_history you could run this:

# $ZSH_CUSTOM should already be automatically set to $ZSH/custom
# but you can customize the location in your ~.zshrc.
# ie: export ZSH_CUSTOM=~/.zsh_custom

# set up lib in omz custom area
mkdir -p $ZSH_CUSTOM/lib

# start off with omz version of the file
cp $ZSH/lib/history.zsh $ZSH_CUSTOM/lib/history.zsh

# edit that file and make it what you want
${EDITOR:-vim} $ZSH_CUSTOM/lib/history.zsh