pleditor (drawing sheet editor) page border width depends on the width of the last drawn line

Description

The width of the drawn page border seems to depend randomly on the width of the last drawn line.

Bildschirmvideo_von_07.03.2021_12_38_51

Steps to reproduce

1. Draw a new line
2. Change width of that line
3. Observe page border

KiCad Version

Application: KiCad-Zeichnungsblatt-Editor

Version: (5.99.0-9636-g239095717d-dirty), debug build

Libraries:
	wxWidgets 3.1.4
	libcurl/7.71.1 OpenSSL/1.1.1i-fips zlib/1.2.11 brotli/1.0.9 libidn2/2.3.0 libpsl/0.21.1 (+libidn2/2.3.0) libssh/0.9.5/openssl/zlib nghttp2/1.43.0

Platform: Linux 5.10.19-200.fc33.x86_64 x86_64, 64 bit, Little endian, wxGTK, gnome, wayland

Build Info:
	Date: Mar  7 2021 12:43:49
	wxWidgets: 3.1.4 (wchar_t,wx containers) GTK+ 3.24
	Boost: 1.73.0
	Curl: 7.71.1
	ngspice: 33
	Compiler: GCC 10.2.1 with C++ ABI 1014

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
	KICAD_SPICE=ON
	KICAD_STDLIB_DEBUG=OFF
	KICAD_STDLIB_LIGHT_DEBUG=OFF
	KICAD_SANITIZE=OFF