hobgoblin: .html() output for <hr/> differs for shallow() vs. render()

Testing a minor component that renders only <div><hr /></div>. I was attempting to evaluate testing with outputs from shallow() vs. render() when I found differences in the results from .html().

The shallow renderer's shallowWrapper.html() returns <div><hr/></div>

The static renderer's renderWrapper.html() returns <div><hr></div>

Is static rendering with cheerio causing the strange "how do we represent self-closing elements" differences?

Is there a mention in the docs that nothing is guaranteed about outputs from .html() and .text()?

Is there a stated/doced bias for which renderer to prefer?

Should I tell my consistency hobgoblin to go join the troll under the nearest bridge?