Editor crashed when returning the license

Steps to Reproduce:
1. Click on Help > Manage Licence > Return Licence > Confirm
2. Click "No" button in the Confirm Pop-up
3. Click on Close button on the license window
4. Observer the Crash

Reproduces on: 2018.1.0b5, 2018.1.0b4, 2018.1.0a1, 2017.3.0f3, 2017.2.0f3
Working on: 2017.1.2f3

Environment : Occurs on Windows and Mac

Note: Returning of License using Unity Hub does not crash the Editor.