Just shot you a reply back, but wanted to post it here as well in case this comes up for anyone else as well...
It seems to have something to do with the original page itself. Something seems wonky. I don’t know if it is something in that original content that got pulled over, or the page itself, but something is definitely amiss.
The stacks themselves seem to be working ok. And if I delete the Glide stack from the "Christmas" page and copy over the one from the "Untitled" page it works fine.
I’m not seeing any errors being thrown in the web inspector either. My only guess, unfortunately, is that is has something to do with the content being pulled over from the other project file or something with that particular content that was pulled over.
If you’re building a new site anyway, you might want to just start with fresh content instead of dragging over pages. Might save you the headache of oddities like this. Just my 2 cents.