[JENKINS-26634] User should be able to select items always shown for single-item axises

As a test writer, I want to be able to use matrix build as Nx1 configuration so that entries from both axises are shown. Currently the plugin hides items if one axis only has a single element. This should be optional because not everyone might want these items shown. I have seen fake items that are not built at all just so the real item is displayed.

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Originally reported by nanonyme, imported from: User should be able to select items always shown for single-item axises

• assignee: kohsuke
  
• status: Open
  
• priority: Major
  
• component(s): matrix-project-plugin
  
• resolution: Unresolved
  
• votes: 0
  
• watchers: 2
  
• imported: 2025-12-06
  

As a test writer, I want to be able to use matrix build as Nx1 configuration so that entries from both axises are shown. Currently the plugin hides items if one axis only has a single element. This should be optional because not everyone might want these items shown. I have seen fake items that are not built at all just so the real item is displayed.

Start by reading the matrix-project-plugin behavior that hides entries when one axis has a single element, then identify how matrix-axis configuration is represented. The change is done when users can optionally keep those single-item-axis entries visible while existing default behavior remains available; no specific file or test is named.

Written by the indexing model from the issue text.