Since the last update the toolbar on write mail has disappeared and can only be reinstated using the alt key - and this has to be done for every email.
While on the screen you're showing, press the Alt key > press the V key > click Toolbars > click Menu Bar. Do the same steps to enable the Composition Bar. Then the Menu Bar and Composition Bars will always be visible. If you don't want the Menu bar visible all the time, disable it after enabling the Composition Bar