$ xdg-desktop-menu install Onivim2.desktop 
xdg-desktop-menu: filename 'Onivim2.desktop' does not have a proper vendor prefix
A vendor prefix consists of alpha characters ([a-zA-Z]) and is terminated
with a dash ("-"). An example filename is 'example-Onivim2.desktop'
Use --novendor to override or 'xdg-desktop-menu --manual' for additional info.