IE 11 Settings Changed After This Patch Tuesday ?

I noticed two changes that were made to my desktop's IE 11 browser after this patch Tuesday's updates (which is the only thing that has changed that I can think of).

First, I had a separate row for the IE11 title bar on top, followed underneath with a row for all the open tabs. This changed to having both in the same row (and the toolbars were locked all the time).

Second, a center click on my mouse on a link would open that new link immediately into a new tab. This changed by opening a complete separate browser session instead of a new tab in the open session.

These changes only started after I shut down the computer for the evening and restarted in the morning. I was able to reset the IE 11 preferences to restore normal behavior, but I can't understand how they changed on their own (especially with the toolbars having been locked with respect to item 1 above).

I don't know if the changes had anything to do with any update installed, but I did not make the changes, and no one else uses my computer. Anyone have any ideas or a similar experience? Checked for viruses . . . none found.

EDIT: I also had a pending Java Update during that time, but when I went to install it, it reported that I already had the latest version and nothing installed.