I tested this by putting a ```raise``` statement into the file ```src/clients/inst_worker_initial.rb``` ; there came up a dialog with a ```OK``` button, the hook got executed after it's been confirmed.

The use case with the red popup is valid for the ```ProductControl``` file from ```yast2``` (the pull request will follow), and it's similar like here: first there is a popup with single ```OK``` button; after clicking it there is raised the red popup with a variety of buttons. The hook is executed before the red popup thing appears.