Kit selection page lists kit twice after removing one of the former listed kits

Steps to reproduce:

• have 2 kits configured with different Qt versions (I had a MSVC2017 5.11 and a 5.10 MinGW if it matters)
• open an existing project (after removing any .user* files) to "open" the kit selection page
• click on 'Manage Kits...' button
• remove the Qt version and the respectiv kit (if it matters - this was my default kit as well)
• close the options by using 'OK' (or 'Apply' first - whatever you like)
• check the kits selection page now

Current result:

• the one and only kit is now listed twice (at least inside the main window - on the left side (Build & Run and so on) it is listed only once)
• selecting both of them creates a single configured kit for the project, but configures the build configurations twice (I've got now Release, Debug and Profile as usual, and additionally the same configurations with a '2' suffix)