Installer hangs if network connection is blocked

QtCreator installer hangs for a long time on the starting screen (see the screenshot) if network access is restricted.

In my country (Russia), network access to some sites is restricted, and one of such sites is https://codereview.qt-project.org/. The site simply doesn't open, the browser is hanging in the "connecting" state until it times out. I suspect, this may have something to do with the QtCreator installer.

This issue is asking for an option to proceed with a completely offline installation. Currently, the network requests are hanging and there seems to be no way to cancel them to continue the installation process.