We try to use the "Branches to build" setting of the GIT plugin with variable substitution.
That it should be possible and work is stated in the inline help for this parameter:
We have setup our job with the flag "Prepare environment to run" and added following parameter as "Properties Content":
In the field of "Branches to build" we tried to use
We have also tried
We can see for a specific build that the parameter is available as "Environment Variable".
The job log looks like this (where the parameter is not replaces by the content):
We expect, that the variable is replaced by its content and used in the git command invocation.