wezterm/docs/config/lua/keyassignment/ActivateTabRelative.md

ActivateTabRelative

Activate a tab relative to the current tab. The argument value specifies an offset. eg: -1 activates the tab to the left of the current tab, while 1 activates the tab to the right.

local wezterm = require 'wezterm';
return {
  keys = {
    {key="{", mods="ALT", action=wezterm.action{ActivateTabRelative=-1}},
    {key="}", mods="ALT", action=wezterm.action{ActivateTabRelative=1}},
  }
}

See also ActivateTabRelativeNoWrap