Problem

When:

1. using a milestone before an input,
2. and one (or more) of the build is waiting for user input,
3. and a failure in another build happens,
4. the builds waiting for input will abort older jobs.

Duplication Steps

1. Create a job with the following code:

   node {
    milestone label: 'test1', ordinal: 1
    input 'test'
    sh 'exit 1'
   }
   

2. Trigger two builds.
3. Approve the newest job (#2) to continue.

Current behavior

The newer job (#2) will fail, the older job (#1) will be aborted and display Superseded by <jobname>#<build_num> which is pretty confusing.

Expected behavior

The newer job (#2) will fail, while the older job (#1) will wait for confirmation.

Workaround

Removing all milestone before the input seems to solve the issue.

node {
 input 'test'
 sh 'exit 1'
 milestone label: 'test1', ordinal: 1
}

Might be tangeantially related to JENKINS-41604