React will issue a warning in dev if you use contentEditable with children. This can be suppressed with suppressContentEditableWarning.
https://github.com/facebook/react/blob/85dcbf83/src/renderers/dom/shared/ReactDOMComponent.js#L187-L193
This should be easy enough to enforce for most cases with a linter rule.
Bad:
<div contentEditable>
Children
</div>
Good:
<div contentEditable />
<div contentEditable suppressContentEditableWarning>
Children
</div>
Name: dom-elements-no-content-editable-with-children?
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Name:
dom-elements-no-content-editable-with-children?