Thanks, Mofi, for your reply. (I've been swamped, and am just getting back to this issue.)
Yes, I confirmed that I am using UE 15.00.0.1043.
Thanks for the link to the Font Size topic. I tried adding those two lines of code to my INI file, but it seemed to have no effect. I tried changing the font family as well as the size, and saw no changes. (Yes, I closed the application and restarted between changes.)
Another interesting thing I noticed is that if my file name is short, <= 8 characters (plus extension), then I can see the asterisk on the active tab. If I rename to 9 characters, the file name will "overflow" and I lose the asterisk. Also, having the "Close Tab Button" on the active tab or turned off makes no difference. UE is smart enough to add extra space for that button.
Oh, well! I will learn to live with it.
Thank you again for your input.