P.S. Clicking the blank white "preview" takes me there, but I'd like to SEE the preview in the new tab screen.

Is that a link to a http connection or is there a secure https connection used to access that page?

The preview thumbnail is created from the cache, so that page needs to be in the cache and the page might have a no-cache or other response header to prevent this.

I spend a LOT of time on that site as an admin. And in fact, the site was already open in another tab when I clicked the "+" to open a new tab with the blank preview. It worked properly until yesterday, and I'm not aware of any changes I made that should have affected the preview. Other frequently viewed pages on that site DO show up as previews if I unpin something from the new tab page. ALL available previews have SOMETHING pinned to them, because I want to see the "permanent" frequent sites on that screen, and not have them displaced by stuff that I'm temporarily visiting frequently.

Oh, not responsive enough to your question. It's not https. It's simply http://mb.nawcc.org/

I have no idea why, but earlier this AM the preview was still missing. And NOW it's there again. And I don't think I did anything to change the behavior.

Thanks for your help.

I see these items in the HTTP response headers if I use the Live Http Headers extension:

Cache control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache

So that page is rather aggressive in not wanting to be cached.

I think I'll pass that along to more experienced admins on our site. Maybe changing that will speed things up for our worldwide users.

THANKS!!!!!!!!!!!