Presently the new Editor window tab design is
layed out like this:

[Tab Name][Tab Name][Tab Name][<][>][V]

It should be on the left:

[<][>][V][Tab Name][Tab Name][Tab Name]

Rationale:

I'm working on a file. I realize a have to edit a
file I remember I was working on previously, but I
can't immediately see it on the screen.

Since the tabs are generally in chronological
order, I click the leftmost tab to see if its the
one I want. I do this a couple of times.

If I don't find the tab I want after a couple of
tries, I give up and go to use the menu to find
the file I want to work on.

Problem: the Tab selection menu is all the way
over on the right, but my mouse is all the way
over on the left.

I realize one could make a reverse argument: if
one were paging through the tabs at the right hand
end, having the menu on the left hand end will be
less usable. However after a month or so on 3.6 I
find this doesn't happen often. Almost always I'm
working on a file I opened more recently (so it's
tab is further to the right) and looking for a
file I opened long ago (so its tab is on the
left). Thus I always end up searching backwards
through the tabs.

Solution: put the tab dropdown menu at both ends,
or move it to the left.