[JENKINS-65818] Conditional BuildStep plugin fails with Jenkins version 2.289.1

After upgrading Jenkins from version 2.263.3 to version 2.289.1, the Conditional BuildStep plugin fails with the following messages:

Exception caught evaluating condition: [java.lang.RuntimeException: Error creating extended parser class: null], action = [Fail the build]

Build step 'Conditional steps (multiple)' changed build result to FAILURE

Build step 'Conditional steps (multiple)' marked build as failure

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Originally reported by muilwyk, imported from: Conditional BuildStep plugin fails with Jenkins version 2.289.1

• status: Open
  
• priority: Blocker
  
• component(s): conditional-buildstep-plugin
  
• resolution: Unresolved
  
• votes: 1
  
• watchers: 3
  
• imported: 20260107-133739
  

Raw content of original issue

After upgrading Jenkins from version 2.263.3 to version 2.289.1, the Conditional BuildStep plugin fails with the following messages:


Exception caught evaluating condition: [java.lang.RuntimeException: Error creating extended parser class: null], action = [Fail the build]

Build step 'Conditional steps (multiple)' changed build result to FAILURE

Build step 'Conditional steps (multiple)' marked build as failure

• environment: Jenkins 2.289.1 on Windows 10 and Windows Server 2019 with Conditional Buildstep 1.4.1