Currently (2021-10-28), Custom HTML embedded in a Rich Text field (via the Designer) is lost, when retrieved via the API. (Same thing happens with CSV export.) All we see is a plain
<div></div> with no indication that it was ever a custom HTML segment.
I can understand filtering out ill-formed and/or unrecognized HTML on import, as a safety feature. But this is our own content, added through Webflow's development environment. We should be able to get it back out again, just as it was put in.
Even if it takes a different API call to get/set the custom bits, and to know where they belong, it would be better than losing them entirely.
Workaround: set the Rich Text field solely through the API. Then the field contents are accurately retrieved via the API. At least in my latest test case.
You can use the Designer to edit the other fields of the Collection Item. When I did that, the Item Editor was unable to display the Rich Text field accurately, but the Rich Text contents remained as uploaded.
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