FEM: Warp filter is displayed in red

[maxwxyz]

Is there an existing issue for this?

• [X] I have searched the existing issues

Problem description

When a PostFilterWarp is present in the results pipeline, adding any other filter is coloring the entire mesh in red. You have to select the warp filter in the tree once, to display the original colors.

It also renders completely red if you have only one warp filter in the pipeline and double click it in the tree view to edit it again: the mesh is completely red, until you select the warp filter in the tree view (task dialog can be left opened in edit mode of the warp filter)

https://github.com/FreeCAD/FreeCAD/assets/6246609/725c5af0-f695-463f-bdf2-bb04595bdab5

@FEA-eng FYI

Full version info

OS: Windows 11 build 22631
Word size of FreeCAD: 64-bit
Version: 0.22.0dev.36958 (Git)
Build type: Release
Branch: main
Hash: a041129090b8dcbb8367636840d3c668ef30a933
Python 3.11.9, Qt 5.15.13, Coin 4.0.2, Vtk 9.2.6, OCC 7.7.2
Locale: German/Germany (de_DE)
Installed mods: 
  * BIM 2021.12.0
  * CfdOF 1.25.11
  * Curves 0.6.35
  * dodo 1.0.1
  * fasteners 0.5.20
  * fcVM-WB
  * freecad.gears 1.2.0
  * OpenTheme 2024.4.20
  * sheetmetal 0.4.13

Subproject(s) affected?

FEM

Anything else?

No response

Code of Conduct

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