Shader source not displayed in UI (Properties view)

Steps:

• Create/open a 3D project
• Import shader file to Assets, e.g. the one attached
• Drag and drop shader file from Assets to Navigator
• -> shader component created, but in Properties, shader "Source" is empty. In code view source is set correctly
•     Shader {         id: simple         shader: "shaders/simple.frag"         stage: Shader.Fragment     }