System Information
Operating system: Linux-5.17.15-1-MANJARO-x86_64-with-glibc2.35 64 Bits
Graphics card: AMD VERDE (LLVM 13.0.1, DRM 2.50, 5.17.15-1-MANJARO) AMD 4.5 (Core Profile) Mesa 22.1.1

Blender Version
Broken: 3.0.1, version: 3.3.0 Alpha, branch: master, commit date: 2022-06-18 22:14, hash: rB575884b82786
Worked: (newest version of Blender that worked as expected)

Short description of error
In Edit or Texture Paint mode, undo does not work in the Shader editor. Sometimes, undo stops having any effect on the nodes, sometimes it just takes multiple undos to undo a single change (no reproducible example for that at the moment). I'm using global undo.

Exact steps for others to reproduce the error
In the default scene,

• enter edit mode
• open a shader editor
• select the Principled BSDF node and either
  • Alt-drag to disconnect it from the Material Output node
  • or add a label to the node
  • or add a brick texture node and connect it to the Principled BSDF color input
  • or deleting the Principled BSDF
• 4x Ctrl-Z takes you out of edit mode (2x undo in case of the changed label) but does not reconnect the Principled BSDF to the Material output (if you are in Object mode, pressing once will reconnect the nodes) or return the label to its prior state

In Texture Paint mode, undo will not take you back to object mode.