Firefox Community Forum

I’m the owner of a Korean webtoon platform at https://newtoki.com.co/, and I’ve recently run into a strange, intermittent issue that only seems to happen in Firefox.

Here’s the situation:

The site loads fine most of the time, but occasionally when I (or some of my users) try to open it, Firefox throws a “Secure Connection Failed” message with an error code like SEC_ERROR_OCSP_INVALID_SIGNING_CERT or sometimes NS_ERROR_NET_RESET.

This happens randomly — sometimes on the homepage, sometimes when navigating to a category or content page.

I’ve tested in Chrome and Edge, and the site loads without any errors there.

Steps I’ve taken so far:

Cleared Firefox cache and cookies, restarted the browser — no change.

Tried in Firefox’s Troubleshoot Mode — still happens occasionally.

Contacted my hosting provider — they checked the server logs and SSL configuration and told me everything is fine on their side.

Verified my SSL certificate chain with an online checker — no obvious issues found.

Additional details:

I’m based in Korea and use the site daily for uploading and managing content.

Some users outside Korea have also reported the same error, but not consistently.

The issue started about a week ago, without any major changes to the site’s code or hosting environment.

I’m wondering if this could be related to Firefox’s OCSP stapling checks, a caching issue, or something about how my CDN is serving resources.

Has anyone seen similar behavior in Firefox with otherwise valid HTTPS sites? Any suggestions on what I can check next would be greatly appreciated.

Thank you in advance for your help!