Default Shader Graph template thumbnail appears blurry and pixelated

Steps to reproduce:

1. Create a new Unity project
2. Open the "Create new Shader Graph Asset" window (Console window > right click > Create > Shader Graph > From Template...)
3. Select any template and click the "Create" button
4. Select a newly created shader graph item in the "Project" window
5. Go to the "Inspector" window and check "Use As Template"
6. Expand the "Template" section
7. Enter the template name and save the changes
8. Open the "Create new Shader Graph Asset" window again
9. Select the newly created template and observe its thumbnail

Actual results: Thumbnail appears blurry and pixelated

Expected results: The default Shader Graph template icon should appear sharp, clear, and properly rendered

Reproducible with versions: 6000.5.0a5

Not reproducible with versions: 6000.5.0a4

Tested on (OS): macOS - Tahoe 26.2