I had 'rewrite titles' checked, and it turned the title in the tab into the literal tags:
%post-title% | %blog-title%
it did the same when 'sharing' posts to Facebook- using %post-title% | %blog-title% as the post title.
so I unchecked it, and the tab title went back to the default, correct post titles
EXCEPT, the facebook post titles continue to say: %post-title% | %blog-title%
where can I change this back to un-rewriting the title!?