I know this request is already open by someone else, but it is from two years ago and this feature is needed now more than ever, most people have the extension "AppIndicator and KStatusNotifierItem Support" installed and some more, the runcat icon adds yet another icon to the right box, making it have too many icons. I used to have the extension "top bar organizer" deal with that, but it is unusable nowadays.

This is definitely a user issue, but it would be nice to be able to define the location of the icon. (be right, left, or center).

For me personally, I love to have it in the center, it does not give the same charm anywhere else.