Ref: https://github.com/facebook/react/issues/631#issuecomment-214909216

It's a little surprising that the codepath is even being hit, maybe that's a bug too, but there should clearly be some sort of `if` check in that area.

if (contentToUse != null) {
        
        ret = escapeTextContentForBrowser(contentToUse);
        if (__DEV__) {
          setContentChildForInstrumentation.call(this, contentToUse);
        }
      } else if (childrenToUse != null) {
        var mountImages = this.mountChildren(
          childrenToUse,
          transaction,
          context
        );
        ret = mountImages.join('');
      }
    }
    if (newlineEatingTags[this._tag] && ret.charAt(0) === '\n') {
      
      
      
      
      
      
      
      
      
      
      return '\n' + ret;
    } else {
      return ret;
    }