To reproduce:
1. Create a new project;
2. Create a cube in a scene;
3. Add Component "LOD Group" to the cube;
4. Attempt to move in between LOD levels by dragging camera icon.

Expected result: you can switch LOD levels by dragging the camera icon
Actual result: you cannot drag camera icon to switch LOD levels

Reproduced with: 2019.2.0b10, 2019.2.0f1, 2019.2.1f1, 2019.2.3f1, 2019.3.0b4, 2020.1.0a6.
Not reproduced with: 2018.4.4f1, 2019.1.14f1, 2019.2.0b1, 2019.2.0b9.

Tested and reproduced on OSX;
Not reproducible on Windows.