Line breaks not always appearing in rendered output

[RobertStanyon]

As of 1.0.74, line breaks in the markdown source are not always resulting in line breaks appearing in the rendered output. The rendered output of

      <MathpixLoader>
        <MathpixMarkdown text={"<span class=\"\">a</span>\n\n<span class=\"\">b</span>"} />
        <hr/>
        <MathpixMarkdown text={"<span class=''>a</span>\n\n<span class=''>b</span>"} />
        <hr/>
        <MathpixMarkdown text={"<span class=\"\">a</span>\n\n<span class=\"\">b</span>"} htmlTags />
        <hr/>
        <MathpixMarkdown text={"<span class=''>a</span>\n\n<span class=''>b</span>"} htmlTags />
      </MathpixLoader>

has changed from the 1.0.73 output:

to the 1.0.74+ output:

when rendered using the react app example provided at https://github.com/Mathpix/mathpix-markdown-it/tree/master/examples/react-app/use-components.

It seems to be specific to having a span with a class which uses double quotes for the class, but does not depend on whether the span tag is actually rendered as HTML or not (i.e. whether the htmlTags option is set).