Steps to repro:

1. Open attached project and 'LightProbeGroupBug';
2. Select Light Probe Group gameobject in the Hierarchy;
3. In the Inspector click on 'Edit Light Probes' button;
4. Switch over to the second Inspector tab;
5. Switch back to the first Inspector tab;
6. In the Inspector click 'Select All' button;
7. Move the light probe group in the scene view by dragging its transform gizmo.

Expected result:
Light Probe group changes its position.

Actual result:
Light Probe group doesn't change its position and transform gizmo is deselected right after clicking on it. See attached video.

Notes:
- Reproducible in 2018.3.0a5, 2018.2.0f2, 2018.1.9f1, 2017.4.7f1;
- Reproducible on Windows and OSX.

Consider checking out https://fogbugz.unity3d.com/f/cases/1061769/ as well.