export powerpoint text box

According to this page, textboxes should become editable when exporting to Powerpoint: https://docs.microsoft.com/en-us/power-bi/consumer/end-user-powerpoint.

However, when I try to export using that function in Power BI Serivce. Text boxes are exported as images instead. 

To be clear: I add the textbox via the toolbar at the top, when editing a report there is a button 'textbox' there.

Anyone knows how to overcome this and get editable textboxes?

Thank you in advance.