Select Generic UI in the project tree and click New > Screen in the context menu.
Then select the Login window template on the Legacy Screen Templates tab.
The new ext-loginWindow.xml file will be created in the Web module and automatically registered in the web-screens.xml.
Since CUBA 7.1 and Studio 9 we have non-legacy templates for Login Screen. And they don't require registration in web-screens.xml.
Environment
Description of the bug or enhancement
Since CUBA 7.1 and Studio 9 we have non-legacy templates for Login Screen. And they don't require registration in web-screens.xml.