Drag and Drop pdf from tab icon

With the free version on Mac, I used to open several files, read it, eventualy emend and, once completed, register and drag from the icon PDF near the name of the file in the Top Tab (where now i can see a star) and drop to an email or a folder or a whatsapp windows, so that the file goes directly there. With last updates i cant do this and I have to remember where the file originally was to open the folder and drag and drop from there or, if i cant find, to register the file in a new position and duplicate it.

Anyone has an idea on how drag the file directly? Hope I explained the problem