How does this differ from https://github.com/zsh-users/zsh-history-substring-search https://github.com/zsh-users/zsh-history-substring-search ? Except that your

How does this differ from https://github.com/zsh-users/zsh-history-substring-search https://github.com/zsh-users/zsh-history-substring-search ? Except that yours seems to be built-in and zsh-history-substring-search is ~800 lines of zsh