[JENKINS-75769] HTML Publisher Plugin not rendering CSS/JS in HTML reports after recent Jenkins update

After a recent update to Jenkins, HTML reports published using the HTML Publisher Plugin are not rendering properly. The `report.html` file opens, but associated CSS and JavaScript files are not applied, resulting in a plain-text or unstructured view.

Previously, the same configuration displayed well-formatted reports. The ExtentReports folder includes subfolders (css, js, media), and the plugin is correctly configured with:

• Directory: ExtentReports/


• Index: report.html

We suspect that CSP or Jenkins core behavior might have changed and is now blocking JS/CSS.

Steps to reproduce:

1. Configure HTML Publisher Plugin with ExtentReports folder

2. Trigger a test run that generates the report

3. Open published `report.html` from Jenkins sidebar

Expected:

• Fully styled report with all assets loaded

Actual:

• HTML loads without CSS or JS, making the report unreadable

This is impacting automation visibility and report sharing. Please advise or suggest a workaround if it's a security change.

Screenshots attached.

---
Originally reported by bhanu9515, imported from: HTML Publisher Plugin not rendering CSS/JS in HTML reports after recent Jenkins update

• assignee: r2b2_nz
  
• status: Open
  
• priority: Major
  
• component(s): htmlpublisher-plugin
  
• resolution: Unresolved
  
• votes: 0
  
• watchers: 2
  
• imported: 20251211-193728
  

Raw content of original issue

After a recent update to Jenkins, HTML reports published using the HTML Publisher Plugin are not rendering properly. The `report.html` file opens, but associated CSS and JavaScript files are not applied, resulting in a plain-text or unstructured view.


Previously, the same configuration displayed well-formatted reports. The ExtentReports folder includes subfolders (css, js, media), and the plugin is correctly configured with:



	
Directory: ExtentReports/

	
Index: report.html



We suspect that CSP or Jenkins core behavior might have changed and is now blocking JS/CSS.


Steps to reproduce:

1. Configure HTML Publisher Plugin with ExtentReports folder

2. Trigger a test run that generates the report

3. Open published `report.html` from Jenkins sidebar


Expected:



	
Fully styled report with all assets loaded



Actual:



	
HTML loads without CSS or JS, making the report unreadable



This is impacting automation visibility and report sharing. Please advise or suggest a workaround if it's a security change.


Screenshots attached.

1 attachment

- [Screenshot (42).png](https://issues.jenkins.io/secure/attachment/64508/Screenshot%20%2842%29.png)
> 

Start by reproducing the issue with an ExtentReports folder containing report.html and its css, js, and media subfolders, then inspect how the published report is served from the Jenkins sidebar. Done means the published report loads its CSS and JavaScript and is fully styled after a Jenkins update.

Written by the indexing model from the issue text.