Am I correct in phrasing your question as: You want only one tab in reading view, and that it will/should relink to the current pane that your editing (even if you have many open tabs)?
I don’t think this is possible out of the box, so you need either a plugin or some command extention to do this for you. I’ve been contemplating myself to make such a command, but haven’t gotten around to it yet. Too much other fun to be done…