Just messed around with some features of Android Studio and got my Component Tree stuck in a different bar than the palette one, as you can see in the pictures:
when both of the bars are closed:
when both of the bars are open:
No matter what I tried I can't get it back to the 2nd inner bar of the palette and it is really impposibble to edit the XML file without it. I tried to do shift + F12 and it only hides and unhides the component tree but does not make it come back to the inner bar as it was the default way.