Wolf wrote:It is the signatures and external images that were not linked using https:// that cause this warning. Not much I can do about it, except disallowing http in external image linking and so breaking all images where the external source offers no encryption.

Everything served by the site itself, including the ad banners, is served via https.
I can independently verify this. For this page, for example, if I sort all the page loads by protocol, with http at the top:
GET 8487.png 304 Not Modified http inara.cz 102.1 KB 217.16.187.13:80 155ms
GET 956.png 304 Not Modified http inara.cz 114.9 KB 217.16.187.13:80 149ms
GET 1758.png 304 Not Modified http inara.cz 110.0 KB 217.16.187.13:80 109ms
GET file.php?avatar=258_1439517985.jpg 304 Not Modified https elitepve.com 23.3 KB 217.160.148.219:443 207ms
GET iframe.html 200 OK https p4-hjxu3goy4l54a-mibuvveh2xr6tqh6-if-v6exp3-v4.metric.gstatic.com 1.6 KB 216.239.32.57:443 41ms
GET l?ebcid=ALh7CaRYaaUlU_tv...ea-0H_bBurhFdMFKGN8aJwV 204 No Content https google.com 0 B 2.127.252.226:443 55ms
GET redir.html 200 OK https p4-hjxu3goy4l54a-mibuvveh2xr6tqh6-if-v6exp3-v4.metric.gstatic.com 175 B 216.239.32.57:443 90ms
GET l?ebcid=ALh7CaRYaaUlU_tv...ea-0H_bBurhFdMFKGN8aJwV 204 No Content https google.com 0 B 2.127.252.226:443 146ms
GET 3324081485367151730 200 OK https tpc.googlesyndication.com 26.5 KB 216.58.210.65:443 83ms
GET redir.html 200 OK https p4-hx75uzoyxalga-vqn4pseirpzcss4b-if-v6exp3-v4.metric.gstatic.com 175 B 216.239.32.57:443 207ms
GET l?ebcid=ALh7CaS_j9ChNNzQ...4zvMLObnLixzZexuoSpIdWd 204 No Content https google.com 0 B 2.127.252.226:443 207ms
GET ads?client=ca-pub-759096...A//elitepve.com&dtd=843 200 OK https googleads.g.doubleclick.net 30.8 KB 216.58.208.66:443 241ms
POST track.php 200 OK https t.skimresources.com 22 B 52.17.190.106:443 293ms
POST link 200 OK https t.skimresources.com 22 B 52.17.190.106:443 213ms
GET ads?client=ca-pub-759096...A//elitepve.com&dtd=580 200 OK https googleads.g.doubleclick.net 30.3 KB 216.58.208.66:443 291ms
GET pla?client=ca-pub-759096...%3A4&plaf=1%3A1%2C2%3A1 200 OK https pagead2.googlesyndication.com 39 B 216.58.208.66:443 45ms
GET arrow_left.gif 304 Not Modified https elitepve.com 49 B 217.160.148.219:443 192ms
GET bg_button.gif 304 Not Modified https elitepve.com 182 B 217.160.148.219:443 175ms
GET icon_back_top.png 304 Not Modified https elitepve.com 2.9 KB 217.160.148.219:443 165ms
GET icons_share.png 304 Not Modified https elitepve.com 40.4 KB 217.160.148.219:443 152ms
GET quote.gif 304 Not Modified https elitepve.com 223 B 217.160.148.219:443 136ms
GET icon_post_target.gif 304 Not Modified https elitepve.com 124 B 217.160.148.219:443 137ms
GET icon_contact.png 304 Not Modified https elitepve.com 340 B 217.160.148.219:443 158ms
GET icons_pagination.png 304 Not Modified https elitepve.com 1.2 KB 217.160.148.219:443 132ms
GET icons_button.png 304 Not Modified https elitepve.com 8.4 KB 217.160.148.219:443 119ms
GET site_logo.png 304 Not Modified https elitepve.com 30.4 KB 217.160.148.219:443 109ms
GET bg_header_big.png 304 Not Modified https elitepve.com 466.2 KB 217.160.148.219:443 99ms
GET ?callback=skimlinksApply...3415a205%23p42886%22%7D 200 OK https r.skimresources.com 349 B 54.229.223.71:443 98ms
GET px.gif?ch=2&rn=1.175155577930899 200 OK https p.skimresources.com 43 B 52.16.242.199:443 180ms
GET px.gif?ch=1&rn=1.175155577930899 200 OK https p.skimresources.com 43 B 52.16.242.199:443 134ms
GET ranks_competent.png 304 Not Modified https elitepve.com 6.9 KB 217.160.148.219:443 165ms
GET file.php?avatar=3317_1448728306.png 304 Not Modified https elitepve.com 3.8 KB 217.160.148.219:443 328ms
GET icon_e_biggrin.gif 304 Not Modified https elitepve.com 467 B 217.160.148.219:443 132ms
GET icon_e_smile.gif 304 Not Modified https elitepve.com 521 B 217.160.148.219:443 111ms
GET file.php?avatar=1851_1444147173.png 304 Not Modified https elitepve.com 11.6 KB 217.160.148.219:443 274ms
GET generic_ElitePvE_sig.png 304 Not Modified https elitepve.com 81.3 KB 217.160.148.219:443 91ms
GET icon_e_sad.gif 304 Not Modified https elitepve.com 531 B 217.160.148.219:443 81ms
GET ranks_master.png 304 Not Modified https elitepve.com 10.1 KB 217.160.148.219:443 67ms
GET a1e9d8be52e37c61ee577dbc75376466?s=90 304 Not Modified https secure.gravatar.com 2.5 KB 192.0.80.240:443 301ms
GET adsbygoogle.js 304 Not Modified https pagead2.googlesyndication.com 13.5 KB 216.58.208.66:443 70ms
GET adsbygoogle.js 304 Not Modified https pagead2.googlesyndication.com 13.5 KB 216.58.208.66:443 27ms
GET stars.png 304 Not Modified https elitepve.com 218.3 KB 217.160.148.219:443 57ms
GET analytics.js 304 Not Modified https google-analytics.com 10.7 KB 216.58.210.14:443 102ms
GET font-awesome.min.css 304 Not Modified https elitepve.com 23.2 KB 217.160.148.219:443 432ms
GET elitepve.css 304 Not Modified https elitepve.com 9.0 KB 217.160.148.219:443 421ms
GET imageset.css 304 Not Modified https elitepve.com 10.2 KB 217.160.148.219:443 411ms
GET colours.css 304 Not Modified https elitepve.com 29.1 KB 217.160.148.219:443 400ms
GET forms.css 304 Not Modified https elitepve.com 7.2 KB 217.160.148.219:443 388ms
GET cp.css 304 Not Modified https elitepve.com 5.9 KB 217.160.148.219:443 376ms
GET buttons.css 304 Not Modified https elitepve.com 7.1 KB 217.160.148.219:443 367ms
GET content.css 304 Not Modified https elitepve.com 14.8 KB 217.160.148.219:443 355ms
GET links.css 304 Not Modified https elitepve.com 3.6 KB 217.160.148.219:443 344ms
GET common.css 304 Not Modified https elitepve.com 22.2 KB 217.160.148.219:443 334ms
GET 87239X1539983.skimlinks.js 304 Not Modified https s.skimresources.com 28.1 KB 185.31.17.192:443 224ms
GET topicpreview.js?assets_version=294 304 Not Modified https elitepve.com 4.8 KB 217.160.148.219:443 366ms
GET abbc3.js?assets_version=294 304 Not Modified https elitepve.com 25.8 KB 217.160.148.219:443 356ms
GET script.js?assets_version=294 304 Not Modified https elitepve.com 128 B 217.160.148.219:443 344ms
GET elitepve.js?assets_version=294 304 Not Modified https elitepve.com 386 B 217.160.148.219:443 334ms
GET jquery.collapse_storage.js?assets_version=294 304 Not Modified https elitepve.com 1.3 KB 217.160.148.219:443 310ms
GET jquery.collapse.js?assets_version=294 304 Not Modified https elitepve.com 4.5 KB 217.160.148.219:443 323ms
GET ajax.js?assets_version=294 304 Not Modified https elitepve.com 11.4 KB 217.160.148.219:443 300ms
GET forum_fn.js?assets_version=294 304 Not Modified https elitepve.com 23.2 KB 217.160.148.219:443 245ms
GET core.js?assets_version=294 304 Not Modified https elitepve.com 43.5 KB 217.160.148.219:443 182ms
GET no_avatar.gif 304 Not Modified https elitepve.com 930 B 217.160.148.219:443 615ms
GET dark.css?assets_version=294 304 Not Modified https elitepve.com 2.6 KB 217.160.148.219:443 205ms
GET scrolltotop.css?assets_version=294 304 Not Modified https elitepve.com 731 B 217.160.148.219:443 190ms
GET abbc3.css?assets_version=294 304 Not Modified https elitepve.com 2.4 KB 217.160.148.219:443 371ms
GET shareon.css?assets_version=294 304 Not Modified https elitepve.com 1.9 KB 217.160.148.219:443 273ms
GET boardrules_common.css?assets_version=294 304 Not Modified https elitepve.com 196 B 217.160.148.219:443 359ms
GET cookie.css?assets_version=294 304 Not Modified https elitepve.com 556 B 217.160.148.219:443 345ms
GET responsive.css?assets_version=294 304 Not Modified https elitepve.com 10.2 KB 217.160.148.219:443 322ms
GET stylesheet.css?assets_version=294 304 Not Modified https elitepve.com 203 B 217.160.148.219:443 141ms
GET stylesheet.css?assets_version=294 304 Not Modified https elitepve.com 641 B 217.160.148.219:443 130ms
GET print.css?assets_version=294 304 Not Modified https elitepve.com 3.0 KB 217.160.148.219:443 70ms
GET viewtopic.php?f=2&p=4288...0cba58b23415a205#p42886 200 OK https elitepve.com 60.6 KB 217.160.148.219:443 602ms
GET iframe.html 200 OK https SPDY p4-hx75uzoyxalga-vqn4pseirpzcss4b-if-v6exp3-v4.metric.gstatic.com 1.6 KB 216.239.32.57:443 38ms
GET collect?v=1&_v=j40&a=206...76040-1&_r=1&z=59767623 200 OK https SPDY google-analytics.com 35 B 216.58.210.14:443 42ms
GET ca-pub-7590967039398538.js 304 Not Modified https SPDY pagead2.googlesyndication.com 109 B 216.58.208.66:443 76ms
GET jquery.min.js 304 Not Modified https SPDY ajax.googleapis.com 32.6 KB 74.125.71.95:443 193ms
GET adsbygoogle.js 304 Not Modified https SPDY pagead2.googlesyndication.com 13.5 KB 216.58.208.66:443 63ms
GET css?family=Sintony:400,700 200 OK https SPDY fonts.googleapis.com 445 B 64.233.184.95:443 167ms
GET css?family=Orbitron:400,500,700 200 OK https SPDY fonts.googleapis.com 298 B 64.233.184.95:443 167ms
GET css?family=Open+Sans:600...ek-ext,greek,vietnamese 200 OK https SPDY fonts.googleapis.com 262 B 64.233.184.95:443 161ms
GET 6.gif 200 OK https p4-hx75uzoyxalga-vqn4pseirpzcss4b-409975-i1-v6exp3-v4.metric.gstatic.com 35 B 216.58.210.46:443 279ms
GET 6.gif 200 OK https p4-hx75uzoyxalga-vqn4pseirpzcss4b-409975-i2-v6exp3-ds.metric.gstatic.com 35 B 216.58.208.67:443 319ms
GET 6.gif 200 OK https p4-hjxu3goy4l54a-mibuvveh2xr6tqh6-456142-i1-v6exp3-ds.metric.gstatic.com 35 B 216.58.208.67:443 167ms
GET 6.gif 200 OK https p4-hjxu3goy4l54a-mibuvveh2xr6tqh6-456142-i2-v6exp3-v4.metric.gstatic.com 35 B 216.58.208.78:443 260ms
GET gen_204?ipv6exp=3&sentin...mg_dt=283&ds_img_dt=476 204 No Content https p4-hx75uzoyxalga-vqn4pseirpzcss4b-409975-s1-v6exp3-v4.metric.gstatic.com 0 B 216.58.210.46:443 80ms
GET gen_204?ipv6exp=3&sentin...mg_dt=299&v4_img_dt=298 204 No Content https p4-hjxu3goy4l54a-mibuvveh2xr6tqh6-456142-s1-v6exp3-v4.metric.gstatic.com 0 B 216.58.210.14:443 154ms
There are only 3 loading over http, and they are all from inara.