[JENKINS-39299] Add support for custom icons for folders

It would be really nice to be able to select a custom icon for different folders. This way, it would be easier to identify a folder by its icon if there are many folders.

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Originally reported by lukasged, imported from: Add support for custom icons for folders

• status: Open
  
• priority: Minor
  
• component(s): cloudbees-folder-plugin
  
• label(s): folders, icons, jenkins, plugin, user-experience
  
• resolution: Unresolved
  
• votes: 6
  
• watchers: 7
  
• imported: 20251211-141027
  

It would be really nice to be able to select a custom icon for different folders. This way, it would be easier to identify a folder by its icon if there are many folders.

environment

```
Jenkins 2.27

Cloudbees Folders plugin 5.13
```