How to add tooltips for toolbar buttons?

Hi Dear Team,
 
Is there a way to add tooltips for the buttons of toolbar(please see the attached screenshot)?
Use case is that we want to remove the label of buttons(e.g. Save/Export) and leave button icon on the toolbar,but when mouse-over on the button, it will prompt out the customized tooltips which preset.
I tried the localization as below but not work(it seems the tooltips of toolbar only supports certain buttons):

localization: {
            toolbar: {
                connect: "Connect",
                connect_elastic: "To Elasticsearch",
                save: "wss",
                tooltips: {
                    connect_elastic: "hahahahwss",
                    save:"ju"
                }
            }
        }

 
From the document it says that there're only a few items support adding a tooltip:

"tooltips": {
            "add_condition": "Add condition",
            "condition": "Condition",
            "cp_text_color": "Text color",
            "font": "Font",
            "font_size": "Font size",
            "remove_condition": "Remove condition"
        }

So there is a way to achieve this? thanks a lot!