The only reason you would not get "format picture" showing up in a context menu is if a picture object is not selected. Context menus are directly based upon, well, context - and the picture object must be checked before the context menu for same will appear when you hit SHIFT+F10, the context menu/applications key, or right click.
As JM Casey has already noted, if actual or emulated right click is used, the mouse pointer itself must be hovering over the selected picture. If it isn't, the moment the right click is performed focus shifts to wherever the actual system mouse pointer is located. The context menu key and SHIFT+F10 are not dependent on mouse pointer position at all, only on what object is currently selected, so it a picture is currently selected the Format Picture is one of the items in the context menu that appears.
Brian - Windows 10 Home, 64-Bit, Version 1809, Build 17763
Explanations exist; they have existed for all time; there is always a well-known solution to every human problem — neat, plausible, and wrong.
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