Certificate expiration date displayed incorrectly in UI (timezone/date format issue)

Checklist

• Have you pulled and found the error with jc21/nginx-proxy-manager:latest docker image?
  • Yes / No
• Are you sure you're not using someone else's docker image?
  • Yes / No
• Have you searched for similar issues (both open and c## Description
• When renewing a Let's Encrypt certificate in Nginx Proxy Manager v2.13.5, the certificate expiration date is displayed incorrectly in the Certificates UI. The date format/timezone conversion appears to be buggy.

• Steps to Reproduce

• 1. Create or renew a Let's Encrypt certificate via Nginx Proxy Manager
• 2. 2. Go to the Certificates section
• 3. 3. Observe the certificate expiration date

• 5. Expected Behavior

• 6. The expiration date should match the actual certificate expiration date (in ISO format: YYYY-MM-DD HH:MM:SS)

• 8. Actual Behavior

• 9. The certificate expiration date is displayed with incorrect date format conversion. When checking the audit log JSON data, the actual expiration is:
• 10. • "expiresOn": "2026-04-12 15:43:30" (April 12, 2026 - correct ~90 days from issue date)
• 12. But in the UI it displays as:
• 13. • "domingo, 12/4/2026, 3:43:30 p. m." (which appears to be DD/MM/YYYY format confusion)
• 15. This suggests the date is being incorrectly converted from the ISO format, mixing up day/month or timezone information.

• 17. Version Information

• 18. • Nginx Proxy Manager v2.13.5 (Latest)
• 19. • Browser: Chrome/Safari
• 20. • Host system: Docker

• 22. Impact

• 23. • Users may believe their certificate is about to expire soon (in 3 days) when in reality it's valid for ~4 months
• 24. • This causes unnecessary alarm and multiple certificate renewals
• 25. • Could lead to service disruptions if users take action based on incorrect expiration dates

• 27. Additional Context

• 28. The certificate itself is correctly issued by Let's Encrypt with proper 90-day validity. The bug is purely in the UI date display/conversion logic.
• 30. Please fix the date formatting to correctly handle ISO format dates and timezone conversions.losed)?
  • Yes / No

Describe the bug

Nginx Proxy Manager Version

To Reproduce
Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior

Screenshots

Operating System

Additional context

Reproduce the issue in the Certificates section using a renewed Let's Encrypt certificate, then compare the audit log's expiresOn value with the rendered UI date. Trace the Certificates UI date-formatting and timezone-conversion entry point; done means the displayed expiration matches the certificate's actual date without day/month or timezone confusion.