For version 11.0 and above, please do one of the following ways to show or hide the ribbon toolbar.
The first method: Click on one of the tabs in Foxit application. In the following figure, I Choose HOME tab. Click the pushpin icon located on the lower-right corner of the ribbon.
The second method: Right-click toolbar and uncheck the Minimize the Ribbon option to have the ribbon displayed.
The third method: On the Foxit screen, press down Ctrl + F11 shortcut keys to show or hide the ribbon bar.