Currently there are no issues in 1.15.3, but I see in the the following:
Fix blank page in Oxygen
Fix conditional logic not running due to window.load event not firing
Fix not show/hide meta box in the front end
Improve code using ES6
I have done a comparison, but don't see anything immediate that stands out. I will include the condition and field array below (gist).
https://gist.github.com/thefrosty/02f59b42a40dcf06026fa0e14124c656
The odd thing is that it looks like the it shows on load (normal), then conditional logic hides it. But the condition (previously working for the page in question) won't show it again, but I can get it to show using WordPress' "screen Options" toggle.
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