So I have been trying to solve this out on my own but, no way,
the UI Builder crashes when I add a Foldout/Dropdown/Enum/Toolbar element (Menu/Button/…), though these elements work just fine outside the UI Builder (if I create them manually in code via ctors new Foldout()).
The error reported is: NotImplementedException: The support of texture format '0' is undefined.
Part of the stacktrace:
UnityEngine.UIElements.DynamicAtlas.IsTextureFormatSupported (UnityEngine.TextureFormat format) (at <...>:0)
UnityEngine.UIElements.DynamicAtlas.IsTextureValid (UnityEngine.Texture2D texture, UnityEngine.FilterMode atlasFilterMode) (at <...>:0)
UnityEngine.UIElements.DynamicAtlas.TryGetAtlas (UnityEngine.UIElements.VisualElement ve, UnityEngine.Texture2D src, UnityEngine.UIElements.TextureId& atlas, UnityEngine.RectInt& atlasRect) (at <...>:0)
UnityEngine.UIElements.UIR.EntryProcessor.ProcessRange (System.Int32 first, System.Int32 last) (at <...>:0)
UnityEngine.UIElements.UIR.EntryProcessor.ProcessHead (UnityEngine.UIElements.UIR.ChainBuilderStats& stats) (at <...>:0)
UnityEngine.UIElements.UIR.RenderChain+VisualChangesProcessor.ConvertEntriesToCommands (UnityEngine.UIElements.UIR.ChainBuilderStats& stats) (at <...>:0)
UnityEngine.UIElements.UIR.RenderChain.ProcessChanges () (at <...>:0)
UnityEngine.UIElements.UIRRepaintUpdater.Update () (at <...>:0)
Editor Version: 2023.1.1f1
Does anyone has a solution, or any idea that may work?