Changing hidden symbol power pin does not update power net connectivity.

Description

Changing the visibility of a symbol power pin that connects two different power net does not update the connectivity. The schematic has to be closed and reloaded before the changes take affect. This can lead to unexpected connectivity. This seems like a pretty serious issue which could lead to shorted power buses if the user is paying close attention.

There is an ERC warning for this but the warning message isn't very clear. I'll file a separate report for that. I've attached a minimal sample project.

power-pin-visibility-issue.zip

Steps to reproduce

  1. Open KiCad and load the provide project.
  2. Open the schematic.
  3. Launch the net highlight tool.
  4. Click on the +5V net. Observe that it is connected to the +3V3 power symbol as expect.
  5. Clear the net highlighting by clicking on any empty space in the schematic.
  6. Select U1 and press Ctrl+E to open the symbol in the symbol editor.
  7. Select the VCC pin and press E.
  8. Check the pin visibility checkbox.
  9. Press Ctrl+S to save the symbol in the schematic.
  10. Close the symbol editor.
  11. Repeat steps 6 through 10 for symbol U2.
  12. Launch the net highlighting tool.
  13. Click on the +5V net. Observe that the +3V3 power symbol is still part of the net. Now that the symbol VCC pins are visible, they should be separate nets.
  14. Save the schematic and close the schematic editor.
  15. Reopen the schematic.
  16. Repeat steps 12 and 13. Observe the nets are now separate as expected.

KiCad Version

Application: KiCad Schematic Editor x86_64 on x86_64

Version: 9.0.2-238-gb1649071e8, debug build

Libraries:
	wxWidgets 3.2.8
	FreeType 2.13.3
	HarfBuzz 10.2.0
	FontConfig 2.15.0
	libcurl/8.14.1 OpenSSL/3.5.0 zlib/1.3.1 brotli/1.1.0 zstd/1.5.7 libidn2/2.3.8 libpsl/0.21.2 libssh2/1.11.1 nghttp2/1.64.0 nghttp3/1.8.0 librtmp/2.3 OpenLDAP/2.6.10

Platform: Debian GNU/Linux 13 (trixie), 64 bit, Little endian, wxGTK, X11, gnome, x11
OpenGL: NVIDIA Corporation, NVIDIA GeForce RTX 3070 Ti/PCIe/SSE2, 4.6.0 NVIDIA 550.144.03

Build Info:
	Date: Jun 18 2025 08:20:01
	wxWidgets: 3.2.8 (wchar_t,wx containers) GTK+ 3.24
	Boost: 1.83.0
	OCC: 7.8.1
	Curl: 8.14.1
	ngspice: 44.2
	Compiler: GCC 14.2.0 with C++ ABI 1019

Build settings:
	KICAD_IPC_API=ON
	KICAD_STDLIB_DEBUG=OFF
	KICAD_STDLIB_LIGHT_DEBUG=OFF
	KICAD_SANITIZE_ADDRESS=OFF
	KICAD_SANITIZE_THREADS=OFF

Locale: 
	Lang: en_US
	Enc: UTF-8
	Num: 1,234.5
	Encoded кΩ丈: D0BACEA9E4B888 (sys), D0BACEA9E4B888 (utf8)