I just discovered the thread <http://www.joomlart.com/forums/topic/user6-mootabs-not-working-on-ie8/“X-UA-Compatible” content=”IE=7″ /> just after <head> in the index.php file in the administrator.
I went to eXtplorer, and opened to edit the index.php file. Of course, it doesn’t have <head>.
So, I went to Extensions, then Template Manager, then Edit Teline II, then edit HTML. That opens another index.php file. I found <head>, placed in the code, and Saved it. Hopefully that works. I don’t have IE8 installed on my Mac, so I can’t test it.
If this works, I hope this explanation helps someone.