We also experienced this issue. We provide a shared library which has global state. Unfortunately, this state get's not restored and thus restarting is not possible. We try to restart the pipeline directly from blue ocean.

As everything anyway needs to be serializable it should be possible to store and restore the pipeline's state. 

abayer I reproduced this. any idea? thanks

This is expected - anything outside the pipeline block definitely won’t be preserved, and shared libraries that have state won’t be preserved either. We’re not actually saving the execution state of the Pipeline, we’re restarting it from the selected stage with all inputs and stashes preserved.

abayer doesn't this make the feature somehow useless?

What's the reason not storing the complete pipeline status as it is probably done during jenkins restarts?

My use case is that I need my step to work differently on restart, so I need to save a value from the previous attempt.

The restart feature is wonderful and flexible but loses all data, so we have currently a mandatory process for all restarts that need some data from the previous attempt:

write to file -> stash (restart) unstash -> read from file

It seems to be a very common use case, so some way of preserving some data will very much enhance the experience with restarts.

Lemme think on this. It may be viable for us to be able to do something like record some information in the previous build explicitly and then be able to refer to that data in the restarted build. Like (and this is really, really hand-wave-y, so don't take this as anything but speculation) this, maybe?

stage('some-stage') {
  steps {
    setPersistentEnv(key: "FOO", value: "abcd")
  }
}
stage('stage-to-restart') {
  steps {
    echo "FOO is ${env.FOO}"
  }
}

Again, totally not sure if that's actually useful or if it's even possible to implement cleanly.