Fix (#4495)

# Description of Changes

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Please provide a summary of the changes, including:

- What was changed
- Why the change was made
- Any challenges encountered

Closes #(issue_number)
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---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md#6-testing)
for more details.

docker/frontend/nginx.conf

@@ -6,6 +6,11 @@ http {
     include /etc/nginx/mime.types;
     default_type application/octet-stream;
 
+    # Add .mjs MIME type mapping
+    types {
+        text/javascript mjs;
+    }
+
     # Gzip compression
     gzip on;
     gzip_vary on;
@@ -90,6 +95,14 @@ http {
             proxy_set_header X-Forwarded-Port $server_port;
         }
 
+        # Serve .mjs files with correct MIME type (must come before general static assets)
+        location ~* \.mjs$ {
+            try_files $uri =404;
+            add_header Content-Type "text/javascript; charset=utf-8" always;
+            expires 1y;
+            add_header Cache-Control "public, immutable";
+        }
+
         # Cache static assets
         location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
             expires 1y;