SSL site not showing green SSL sign in browsers

Hi,
For some 16.04 Ubuntu servers, I am still forced to use v3…
I know that v3 support is closed, but maybe someone else can point me in the right direction…

Even SSL is enabled and a check at https://www.ssllabs.com/ssltest/ is positive the internet browsers (FF or Edge) are not showing the green ssl sign!
So it appears as insecure. I am not sure what is the reason for this…
See below the screenshots.

So any idea why? Please let me know thanks.

ssl_yes-no

v3 ee site: 
nginx 1.14.0, php 5.6.40-6, mysql 10.1.38

Nginx configuration      wp wpfc (enabled)
PHP Version              7.0
HHVM                     disabled
SSL                      enabled
SSL PROVIDER             Lets Encrypt
SSL EXPIRY DATE          Tue Jul 16 16:02:33 CEST 2019

Every page or certain pages? Are you still linking to any resources with http (images, scripts, fonts)?

The green SSL sign is on all pages missing, not only on one or two… ;-?

Same question really :-): Are you still linking to any resources with http (images, scripts, fonts)?

View source on a page, search for http://

Also check external css for http:// links.