Can't portal inside markdown without React hydration warnings

[aeharding]

React (and HTML, for that matter) don't really like it when <div> is inside <p>. This happens when I portal inside markdown (where virtually everything is inside a <p>), for portalling a video, for example.

So, I would like the option to use inline portal element (outputting <span>). Perhaps ELEMENT_TYPE_HTML could be renamed to ELEMENT_TYPE_HTML_BLOCK and add ELEMENT_TYPE_HTML_INLINE

Here's the error for the placeholder. There's another for the portal container. I'll make a PR to fix both of these.

In HTML, <div> cannot be a descendant of <p>.
This will cause a hydration error.

  ...
    <div ref={null} className="Positioned..." style={{...}}>
      <CommentContainer depth={1}>
        <render depth={1} themeName="rainbow">
          <div ref={null} className="Container_..." style={{...}}>
            <ModeratableItemBannerOutlet>
            <div>
              <CommentHeader>
              <div aria-hidden={false} className={"rah-stat..."} style={{height:"auto", ...}} ref={null}>
                <div className={undefined} style={{}} ref={function ref}>
                  <render onClick={function _temp2}>
                    <div onClick={function _temp2} ref={null} className="Content_ci...">
                      <CommentContent item={{id:4411616, ...}} showTouchFriendlyLinks={true} mdClassName="collapse-m...">
                        <CommentMarkdown className="collapse-m..." id="https://le../.">
                          <Markdown className="collapse-m..." id="https://le../." components={{...}}>
                            <Markdown className="collapse-m..." components={{...}} remarkPlugins={[...]} ...>
                              <div className="collapse-m...">
>                               <p>
                                  ...
                                    <Video alt="image" node={{type:"element", ...}} onClick={function onClick} ...>
                                      <span style={{opacity:0}} className="media smal...">
                                        <OutPortal2 alt="image" node={{...}} onClick={function onClick} ...>
>                                         <div ref={{current:null}}>
                        ...
      ...