Fisher is using add instead of install, fisher version 3.2.11
fisher: unknown flag or command "install"
usage: fisher add <package...> Add packages
fisher rm <package...> Remove packages
fisher Update all packages
fisher ls [<regex>] List installed packages matching <regex>
fisher --help Show this help
fisher --version Show the current version
fisher self-update Update to the latest version
fisher self-uninstall Uninstall from your system
Fisher is using
add
instead ofinstall
, fisher version 3.2.11