Prerequisites:
- Have a valid seat-based serial key assigned to User1 (User1 already accepted the seat, and received serial key by email)

Repro:
1. Sign in to the Editor with User2
2. Attempt to activate Editor with a serial key assigned to User1
3. Observe that serial is not accepted, but no error message is shown
4. Sign out from the editor
5. Observe error which was supposed to be shown on Step2

Editor: 5.3.5f1