0.4.8-RC-24-g795c7f7 gcc dbg.
Opera 12.18 from rapps is affected (Opera 9.64 is not affected)
Install the application
And try to uninstall the application again.
ReactOS will hang then reproducibly while running the uninstaller.
The name of the uninstaller is also Opera.exe (like the main app)
I double-checked: the main app was properly closed when I run the uninstall.
It is not possible to kill the uninstallers exe via taskmgr.
With enourmous amount of patience you can open the taskmgr, and try to kill it, but it will never succeed.
It is not possible to complete a clean ACPI shutdown even (although the system still recognizes and logs the incoming request for that.)
It is a very dramatic representation where the 100% CPU-consuming app blocks any real interaction with the system.