My site includes Gametracker banners for my various servers. Recently, I noticed that the banners sometimes all fail to appear. Refreshing the page doesn't help, and neither does clearing my browser cache. All browsers are affected.

The only fix I've found is to navigate to the Gametracker site or directly to one of the banner image URLs, at which point I see a message that begins with: "Checking your browser..." and ends by saying that the check may take up to five seconds. After that, the GT banners on my web site work okay for a while, then the stop working again.

I've tried using both www.gametracker.com and cache.gametracker.com URLs for the images but there's no apparent difference. It looks like you're using CloudFlare and it's configured too aggressively. At this point the banners are so unreliable that I'm looking at alternatives.

This happened because CloudFlare Activated , we talk about that yesterday :
https://www.gametracker.com/forums/forum.php?site=1&post=406877#post406877
https://www.gametracker.com/forums/forum.php?site=1&thread=129358

Is this the Cloudflare thing? Why does it all of a sudden start happening? I get the delay page when I surf to here, and once I remove the 's' from https, the avatars here show up and then my website's server monitors or banners show up.

Just started a few days ago. Driving me crazy. IS there some kind of workaround?

Yes, Cloudflare is temporarily activated.

For your second question, GameTracker does not support https across the entire website. https pages may appear perfectly if you choose to use it.