1) Have a via with a net, say GND.
2) Move a component so a pad with a different net (say +3.3V) is placed over the via
3) "Esc" - the via is now over the component with the original net (GND)
4) "m" to move the via - the net changes instantly to the new net +3.3V.
5) put the via down somewhere
6) Ctrl-z - the via goes back to its previous position, but keeps the new net
7) Ctrl-z - the part goes back to its previous position, but the via still keeps the new net
I'm thinking this is "high", as it's possible to silently change via nets this ways and it cannot be undone.
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Application: pcbnew
Version: (5.1.2-20-g7bafc5fa8-dirty), release build
Libraries:
wxWidgets 3.0.4
libcurl/7.64.1 OpenSSL/1.1.1b zlib/1.2.11 libidn2/2.1.1 libpsl/0.20.2 (+libidn2/2.1.1) libssh2/1.8.1 nghttp2/1.36.0
Platform: Linux 5.0.12-arch2-1-ARCH x86_64, 64 bit, Little endian, wxGTK
Build Info:
wxWidgets: 3.0.4 (wchar_t,wx containers,compatible with 2.8) GTK+ 3.24
Boost: 1.69.0
OpenCASCADE Community Edition: 6.9.1
Curl: 7.64.1
Compiler: GCC 8.3.0 with C++ ABI 1013
Build settings:
USE_WX_GRAPHICS_CONTEXT=OFF
USE_WX_OVERLAY=ON
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
This threw me for a loop today.
I had moved a 40 pin header out of the way to see underneath for a sec, and it changed a bunch of vias in a critical subcircuit.
A simple undo moved the header back, but the via nets remain changed.