Why do I get below screenshot error when trying to edit the properties of a Date Picket in component view? Anyone has this issue before?

I'm not running anything, i'm just trying to edit and I get below error

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I had to recreate application after somehow loosing developer toolbar, getting malfunctioning charts, and data picker not displaying properly, all for no reason I know.
I am using unviersal theme 42 and standard template
As you can see (below screenshot), running works - zero error. I'm only attempting to edit property page on date picker and I get such an error.

Can some please tell me they've encountered this before and fixed it?