How to reproduce:
1. Create a new project
2. Install the UI Toolkit package
3. Select Window > Analysis > Profiler (Standalone Process)
4. Observe the Console

Expected result: There are no errors present
Actual result: Multiple errors appear in the Console

Reproducible with: UI Toolkit 10.0-preview.11 (2020.3.13f1), 1.0.0-preview.14 (2020.3.13f1, 2021.1.14f1)
Not reproducible with: 2021.2.0b2, 2022.1.0a1
Cannot test with: 2018.4.36f1, 2019.4.28f1 (the package is not supported)

Notes:
- The issue doesn't reproduce without the package
- The following errors are displayed in the Console:
Multiple scripted importers are targeting the extension 'uxml' and have all been rejected

Multiple scripted importers are targeting the extension 'uss' and have all been rejected

Multiple scripted importers are targeting the extension 'tss' and have all been rejected

ArgumentException: An item with the same key has already been added.

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.FieldAccessException: Field `UnityEngine.UIElements.TextDelegates:ImportDefaultTextSettings' is inaccessible from method `UnityEditor.UIElements.Text.TextDelegates:InitializeDelegates ()'

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.FieldAccessException: Field `UnityEngine.UIElements.TextHandleFactory:CreateEditorHandle' is inaccessible from method `UnityEngine.UIElements.Text.TextCoreHandle:InjectTextCoreHandle ()'

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.FieldAccessException: Field `UnityEngine.UIElements.TextDelegates:GetFont' is inaccessible from method `UnityEngine.UIElements.Text.TextDelegates:InitializeDelegates ()'

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> UnityEngine.UnityException: The MakeClientFunc has already been registered. Registration denied.

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> UnityEngine.UnityException: The MakeDropdownFunc has already been registered. Registration denied.

FileNotFoundException: No symbol found for file: E:\Unity\2021.1\2021.1.14f1_51d2f824827f\Editor\Data\Managed\UnityEngine\UnityEditor.UIElementsModule.dll