[JENKINS-47370] Unable to override global envs after update to 2.1.4

We have a global setting of JIRA_URL=jira.acme.com

In some jobs we override this in the "Prepare an environment for the run" section to JIRA_URL=jira-staging.acme.com

After upgrading to 1.24 this stopped working. The effective value as seen in shell scripts is jira.acme.com

Setting the value in a "Inject environment variables" build step also has no effect.

The only thing that has an effect is to set the value inside the shell script.

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Originally reported by jbochenski, imported from: Unable to override global envs after update to 2.1.4

• status: Reopened
  
• priority: Blocker
  
• resolution: Unresolved
  
• imported: 2022-10-20
  

Start by reproducing the environment precedence problem in a Jenkins job using the "Prepare an environment for the run" section and the "Inject environment variables" build step after the reported upgrade. Compare the effective JIRA_URL in shell scripts with the global and job-level values; done means job-level overrides take effect without setting the variable inside the script.

Written by the indexing model from the issue text.