Using the Application Launcher set in Desktop Settings > Mouse Actions, applications are always shown by Description Only. I think it would be a useful addition to allow them to be shown by name, or indeed by the other options available in the Application Launcher Widget.
This is a bug in Plasma 5 I'm affected by as well, the usability is essentially lost entirely for me so I simply don't use it anymore. I just checked it in Plasma 4.14.x and this is not an issue . . . while it is not configurable in 4.14.x either, it defaults to application Name instead of Description. Name being the default is logical functionality so I wouldn't consider it a bug in that scenario. - http://michaeltunnell.com/images/linux/kde/mouse-action-menu-plasma-4.png In Plasma 5, the description is used instead and since there are no options to configure this feature in Desktop Settings > Mouse Actions or System Settings it makes the desktop application launcher difficult to use. http://michaeltunnell.com/images/linux/kde/plasma-5.5-mouse-action-launcher-menu-bug.jpg I'd prefer to have the ability to choose how the items are displayed in the same way that the Plasma Widgets have but I'd be satisfied personally if the default setting was Application Name.
Same issue here (openSUSE Leap, kf5 5.20). Quite anoying, it makes the menu almost useless to start applications of which you don't already know where they are in the tree. Why still 'unconfirmed'?
*** This bug has been marked as a duplicate of bug 358423 ***