A row that opens shows a pointing hand when the pointer is over it. Press it, or press Tab to reach it and then Enter or Space.
The buttons at the end of a row, such as More (the three dots), the pencil, the bin and Download, always show. This is the same on a computer, a tablet and a phone.
Where More would hold only one thing to do, the row shows that one button instead, named for what it does. Point at it to read its name.
