PDF plot missing wires

Description

The attached schematic, when plotted to PDF, results in a PDF with no visible wires.

Schematic: gfx.kicad_sch

Generated PDF: gfx.pdf

Screenshot of generated PDF, as rendered by evince 3.36.0: pdf-screenshot

Also confirmed in okular 1.10.0

Steps to reproduce

1. File → Plot → PDF → Plot All Pages

KiCad Version

Application: Eeschema
Version: (5.99.0-1648-gc66bf3df6), release build
Libraries:
    wxWidgets 3.0.5
    libcurl/7.70.0 OpenSSL/1.1.1g zlib/1.2.11 libidn2/2.3.0 libpsl/0.21.0 (+libidn2/2.2.0) libssh2/1.9.0 nghttp2/1.40.0
Platform: Linux 5.6.11-arch1-1 x86_64, 64 bit, Little endian, wxGTK
Build Info:
    Build date: May 12 2020 01:01:06
    wxWidgets: 3.0.5 (wchar_t,wx containers,compatible with 2.8) GTK+ 3.24
    Boost: 1.72.0
    OpenCASCADE Technology: 7.4.0
    Curl: 7.70.0
    Compiler: GCC 9.3.0 with C++ ABI 1013

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