*.user files are not portable between different machines

The *.user files contain a generated project configuration ID and a similar generated ID for each kit.

E.g.:
<value type="QString" key="ProjectExplorer.ProjectConfiguration.Id">

</value>

These IDs seem to be machine dependent, and it is not possible to open a *.user file with QtCreator on a different machine, so that most of the original settings (project configurations assigned to kits) do not get lost.

I could not find an easy way for porting a *.user file, other than creating an empty project with empty kits on a new machine and merge the new IDs into the original *.user file.

This is quite tedious and there seems to be no obvious reason for binding the *.user configuration files to a given machine.