Comment 3 for bug 1793393

I'm sorry, I wasn't aware that it's already there. At the time of writing there was no such entry in cosmic which is why I assumed there's no such search action.

Now I see that the config file you linked to does not take any effect on default search actions. It seems that it's being ignored and all search actions available in cosmic are taken from here
https://git.xfce.org/panel-plugins/xfce4-whiskermenu-plugin/tree/panel-plugin/settings.cpp#n182