When running the installer, cancel it in the middle of the download. Notice that it still tries to launch apprunner at the end. It should just quit all together.
This bug depends on bug #13985 being fixed.
Why would this depend on 13985? That one only applies when XPInstall itself is doing the downloading. XPInstall doesn't know when the install wizard downloads are cancelled.
I updated the wrong bug. Clearing the dependency.
verified on build 1999092112
Updating component from Install Wizard to Installer