Gray triangle on firefox over HTTPS

Question

I've been searching on the net for a while now but don't really seem to find the solution.

I have an TLS connection to app.spiderdoc.co that works on Chrome and Safari but I have a minor issue on Firefox.
I already had the error sec_error_unknown_issuer, which I fixed by providing the intermediate chain certificate.
So, I don't know where that could be coming from. I removed every requests to external resources to no success.

I also found this resource on security.stackexchange but I don't really know how to fix the warning

Answer 1

Looking at the URL with the latest FF beta I see:

So it looks like it objects to the support of RC4 as a TLS cipher, which is a fair enough point, but a quick Google did not confirm that FF actively detects this potential problem.

Disable support for that cipher on your web server and see if that rectifies the problem.