Operating system: Windows-10-10.0.18362 64 Bits
Graphics card: GeForce GT 750M/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 417.71
Broken: version: 2.80 (sub 75), branch: master, commit date: 2019-07-29 14:47, hash: rBf6cb5f54494e
Short description of error
[I was testing the archipack and archimesh add ons, I placed a window to configure its parameters and duplicated it, at the beginning it allowed me to duplicate it without problems a couple of times, I left running in the blender background to look for some information for 10 minutes and when I return to continue working on the file, blender did not allow me to duplicate it or create new materials in the shader editor.
I opened a new file and it kept giving me the same error]
Exact steps for others to reproduce the error
[1.- Open blender and activate archimesh or archipack
2.- Erase the cube and place a window in the center
3.- Duplicate that window a couple of times and check the materials in the shade editor
4.- Leave blender in the background for 10 minutes
5.- Return to work with blender and try to rotate and duplicate the elements that exist in the workspace or create new elements.
(Especially selected by the empty)
6.- Always keep the editor shader open and when you select some geometry or element it shows you the material wrongly or does not allow you to add a new one]
[Based on the default startup ]