Small locator issues on Windows after clicking in Locator

After clicking in locator (QTCREATORBUG-22118), the following strange things happens:

1. You cannot close Locator anymore with the ESC key, only by clicking outside locator
2. Locator stays on top of all windows if you switch Creator in the background
3. Pressing Ctrl+K again opens a second locator on top of the first one

I cannot see such behavior on Linux.