Repro steps:
1. Open user attached project
2. In the Hierarchy, select "Planar Reflection Probe" object and add a Planar Reflection Probe component
3. Reset that component
4. Open the Game window, so the Console window is hidden
5. Go back to the Console window

Expected result: No errors are thrown
Actual result: Quaternion To Matrix conversion failed error is thrown multiple times

Reproducible with: 2018.4.9f1, 2019.2.5f1, 2019.3.0b3, 2020.1.0a4
Could not test with: 2017.4.32f1 (no Package Manager)

Reproducible with package versions: 4.10.0, 5.16.1, 7.0.1

Error thrown: Quaternion To Matrix conversion failed because input Quaternion is invalid {0.000000, 0.000000, 0.000000, -0.000000} l=0.000000
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)