Comment 5 for bug 1740717

My work-around - easy enough that I'd be inclined to call it an OK procedure instead of a work-around:
In Symbol Library Editor with View - Search Tree active, right click on a Symbol and select Duplicate Symbol. You should see a new symbol in bold appear with "_x*" appended to the name of the original Symbol. Double-click the newly created Symbol. Now mouse over the Component Name, hit 'E' and change the Component Name as desired. Save the Symbol. Done. Note that you cannot edit the Component Name through the "T" menu (Component Name will be greyed-out there).

Application: kicad
Version: 5.0.0-fee4fd1~65~ubuntu16.04.1, release build
Libraries:
    wxWidgets 3.0.2
    libcurl/7.47.0 OpenSSL/1.0.2g zlib/1.2.8 libidn/1.32 librtmp/2.3
Platform: Linux 4.15.0-24-generic x86_64, 64 bit, Little endian, wxGTK
Build Info:
    wxWidgets: 3.0.2 (wchar_t,wx containers,compatible with 2.8) GTK+ 2.24
    Boost: 1.58.0
    OpenCASCADE Community Edition: 6.8.0
    Curl: 7.47.0
    Compiler: GCC 5.4.0 with C++ ABI 1009

Build settings:
    USE_WX_GRAPHICS_CONTEXT=OFF
    USE_WX_OVERLAY=OFF
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_WXPYTHON=OFF
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON