How to reproduce:
1. Create a new project
2. Select “Packages/com.unity.textmeshpro/Editor Resources/Shaders/TMP_SDF Internal Editor.shader” shader
3. In the Inspector click the “Compile and show code” or “Preprocess only” option

Expected result: Able to select the “Preprocess only” option and click “Compile and show code”
Actual result: Can not select the “Preprocess only” option or click “Compile and show code”

Reproducible with: 2022.1.0a12, 2022.1.0a13
Not reproducible with: 2019.4.31f1, 2020.3.21f1, 2021.1.28f1, 2021.2.1f1, 2022.1.0a11
Could not test with: 2019.4.31f1 (“Preprocess only” option is missing)

Notes:
- To see the expected result move or copy a shader to the Assets folder and repeat steps 2 and 3 with that shader