[JENKINS-11639] Add "duration difference" column to JUnit "All Tests" section

The "testReport" section at the bottom of the JUnit results page currently shows name, duration, fail, skip and difference in fail/skip from the previous run. A new column showing difference in duration would (I assume) be pretty easy to add and would be very useful.

See attached image for a mockup to clarify what I mean.

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Originally reported by faceless, imported from: Add "duration difference" column to JUnit "All Tests" section

• status: Open
  
• priority: Major
  
• component(s): junit-plugin
  
• resolution: Unresolved
  
• votes: 2
  
• watchers: 3
  
• imported: 2025-11-26
  

The "testReport" section at the bottom of the JUnit results page currently shows name, duration, fail, skip and difference in fail/skip from the previous run. A new column showing difference in duration would (I assume) be pretty easy to add and would be very useful.


See attached image for a mockup to clarify what I mean.

1 attachment

- [durationdiff.png](https://issues.jenkins.io/secure/attachment/21023/durationdiff.png)
> 

Start at the JUnit results page's "testReport" section and compare the existing All Tests columns with the attached durationdiff.png mockup. Trace how the current fail/skip difference is calculated and displayed, then add the duration difference column and verify that the table matches the requested layout.

Written by the indexing model from the issue text.