Symbol editor segfault when changing symbol name on MacOS

Doesn't reproduce for me. Your build is a little old now, maybe try a more recent nightly?

Application: LibEdit
Version: (5.99.0-442-gd20d310fc), debug build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.64.1 SecureTransport (LibreSSL/2.8.3) zlib/1.2.11 nghttp2/1.39.2
Platform: Mac OS X (Darwin 19.0.0 x86_64), 64 bit, Little endian, wxMac
Build Info:
    Build date: Nov 30 2019 14:48:07
    wxWidgets: 3.0.4 (wchar_t,STL containers,compatible with 2.8)
    Boost: 1.70.0
    OpenCASCADE Community Edition: 6.9.1
    Curl: 7.54.0
    Compiler: Clang 11.0.0 with C++ ABI 1002

Build settings:
    KICAD_SCRIPTING=OFF
    KICAD_SCRIPTING_MODULES=OFF
    KICAD_SCRIPTING_PYTHON3=OFF
    KICAD_SCRIPTING_WXPYTHON=OFF
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=OFF
    KICAD_SCRIPTING_ACTION_MENU=OFF
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON
    KICAD_STDLIB_DEBUG=OFF
    KICAD_STDLIB_LIGHT_DEBUG=OFF
    KICAD_SANITIZE=OFF

Tested with current 10.14-nightly, no crash when changing symbol name, but a reproducible segfault when saving the symbol afterwards.

Application: KiCad
Version: (5.99.0-432-gf5ef9671b), debug build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.64.1 SecureTransport (LibreSSL/2.8.3) zlib/1.2.11 nghttp2/1.39.2
Platform: Mac OS X (Darwin 19.0.0 x86_64), 64 bit, Little endian, wxMac
Build Info:
    Build date: Nov 29 2019 08:51:57
    wxWidgets: 3.0.4 (wchar_t,STL containers,compatible with 2.8)
    Boost: 1.69.0
    OpenCASCADE Community Edition: 6.9.1
    Curl: 7.54.0
    Compiler: Clang 9.0.0 with C++ ABI 1002

Build settings:
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_PYTHON3=OFF
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=OFF
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON
    KICAD_STDLIB_DEBUG=OFF
    KICAD_STDLIB_LIGHT_DEBUG=OFF
    KICAD_SANITIZE=OFF

Can't reproduce that, I think it may have been fixed by one of @Jeff's recent commits. Please can you retest with a new nightly?

Application: LibEdit
Version: (5.99.0-454-g089ce90de), debug build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.64.1 SecureTransport (LibreSSL/2.8.3) zlib/1.2.11 nghttp2/1.39.2
Platform: Mac OS X (Darwin 19.0.0 x86_64), 64 bit, Little endian, wxMac
Build Info:
    Build date: Dec 2 2019 23:50:09
    wxWidgets: 3.0.4 (wchar_t,STL containers,compatible with 2.8)
    Boost: 1.70.0
    OpenCASCADE Community Edition: 6.9.1
    Curl: 7.54.0
    Compiler: Clang 11.0.0 with C++ ABI 1002

Build settings:
    KICAD_SCRIPTING=OFF
    KICAD_SCRIPTING_MODULES=OFF
    KICAD_SCRIPTING_PYTHON3=OFF
    KICAD_SCRIPTING_WXPYTHON=OFF
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=OFF
    KICAD_SCRIPTING_ACTION_MENU=OFF
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON
    KICAD_STDLIB_DEBUG=OFF
    KICAD_STDLIB_LIGHT_DEBUG=OFF
    KICAD_SANITIZE=OFF

Tested it yesterday (sorry I couldn't do it any earlier), problem still persists for me.

Is there anything I can check to get more info on what is going wrong?

Application: KiCad
Version: (5.99.0-470-g388d763eb), debug build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.64.1 SecureTransport (LibreSSL/2.8.3) zlib/1.2.11 nghttp2/1.39.2
Platform: Mac OS X (Darwin 19.0.0 x86_64), 64 bit, Little endian, wxMac
Build Info:
    Build date: Dec 5 2019 14:14:16
    wxWidgets: 3.0.4 (wchar_t,STL containers,compatible with 2.8)
    Boost: 1.69.0
    OpenCASCADE Community Edition: 6.9.1
    Curl: 7.54.0
    Compiler: Clang 9.0.0 with C++ ABI 1002

Build settings:
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_PYTHON3=OFF
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=OFF
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON
    KICAD_STDLIB_DEBUG=OFF
    KICAD_STDLIB_LIGHT_DEBUG=OFF
    KICAD_SANITIZE=OFF

@Christoph, for your information - we have switched from Launchpad to GitLab. You can follow your bug report here: https://gitlab.com/kicad/code/kicad/issues/2613

KiCad bug tracker has moved to Gitlab. This report is now available here: https://gitlab.com/kicad/code/kicad/-/issues/2613