Steps to repro:

1. Open attached project and 'test' scene;
2. In the Scene view click on a gameobject.

Expected result:
Gameobject is highlighted in the Scene view and in the Hierarchy (see attached expected.gif video).

Actual result:
Gameobject is not selected. Scene view picking doesn't work (see attached actual.gif video).
Regression introduced in 2018.1.0a2.

Workaround is to select gameobjects in the Hierarchy or drag left mouse button in the scene view and select an area with gameobjects that what you want to select.

Notes:
- Reprodicible in 2018.1.0a3, 2018.1.0a2;
- Not reproducible in 2018.1.0a1, 2017.3.0b8, 2017.2.0p1;
- Reproducible only on Windows 10 (checked); not reproducible on OSX;
- Reproducible only with current scene and project; doesn't repro in a new scene;
- Removing Library folder and restarting project doesn't fix the issue.