framework/base/ActionFilter.php
protected function getActionId($action)
    {
        if ($this->owner instanceof Module) {
            $mid = $this->owner->getUniqueId();
            $id = $action->getUniqueId();
            if ($mid !== '' && strpos($id, $mid) === 0) {
                $id = substr($id, strlen($mid) + 1);
            }
        } else {
            $id = $action->id;
        }

        return $id;
    }
protected function getActionId($action)
    {
        if ($this->owner instanceof Module) {
            $mid = $this->owner->getUniqueId();
            $id = $action->getUniqueId();
            if ($mid !== '' && strpos($id, $mid) === 0) {
                $id = substr($id, strlen($mid) + 1);
            }
        } else {
            $id = $action->id;
        }

        return $id;
    }
Returns an action ID by converting [[Action::$uniqueId]] into an ID relative to the module.
@param Action $action
@return string
@since 2.0.7