Bring back run configurations that are shared between build configurations

QtCreator 17 introduced a change to run configurations. From the release blog post:

A bigger change in Qt Creator 17 is that we made run configurations "part of" the build configuration. Before this, the build configurations and run configurations were completely independent. Now, each run configuration belongs to a certain build configuration, and switching the active build configuration also switches the set of available run configurations. This covers the often requested use case of having different run parameters, like different command line arguments or different environments for different build configurations, such as Debug or Release.

Additionally, you can now copy the values from one run configuration to another, regardless of which build configuration they belong to, with the new "Clone into This" button.

Could we have an option to get the previous behaviour back? For example am way to mark run configurations as shared between all build configurations with an Option (maybe per Project) to make this the default.

In particular, there should be a way to migrate a pre-17 project configuration in such a way that all existing run configurations are carried over with the "shared between all build configurations" flag.

I might be biased, but I'd argue that this should even be the default. I.e. having build-configuration-specific run configurations should be opt-in. I'd wager that the default in the majority of cases is that you want to run the same arguments for all build configuration and you want to easily switch (e.g. between build / release / sanitizer build configs). Having different arguments for different build configurations seems to me like more of a special use case. It's great to have this enabled now, but maybe it's not the right default?

The Clone-to-this button is ok, but it's not a good solution if you have many run configurations and build configurations. It also doesn't do anything to keep the copies in sync.

Motivation: I have projects with 100s of targets and often have 50 or more actively used run configurations (unit test targets, applications, utilities for the various packages in the project). With the ~5 build configurations I switch between (Debug, Release, RelWithDebInfo, variants with sanitizers, etc), duplicating all the run configurations for all build configurations would make the list of run configurations even more crowded.