P: Filmstrip is covering / overlapping filter- and breadcrumb bar

Yes.  I worked with the Adobe support for over 2 hours as mentioned above.  Nothing fixed it and I was told it would be fixed in the next update.   

close up

Hi, this is today's screenshot after I have updated to 2015.10.  

We will look into it. 

Did you restart Lightroom?

Those things didn't even fix it once for me, and I was left with trying to re-create my preferences.  

As Terri mentioned, unchecking tab bar or resetting preferences only solves it once, but it happens again and again.  Am using imac 2014  OS Sierra and latest LR CC. 

Disabling show tab bar doesn't work in my case. Neither does deleting preference file or reinstalling LR.

This issue is caused by when "Show Tab Bar" (Window -> Show Tab Bar) is enabled in Lightroom.

To resolve this, disable  "Show Tab Bar"  (Window -> Show Tab Bar) and restart Lightroom. You can also use the shortcut CMD+SHIFT+T to toggle between these.

Thanks Nikita. Have been trying to figure this out for days now. I am in LR CC and also use Mac Sierra.