Lock PivotTable Field List menu to the side

I was moving around my field list menu and now I can't get it to return to its original location.
In earlier versions of Excel, you could simply double-click the PivotTable Field List menu header and it would return.

It no longer seems to work.

Double click still works for me.

You could also try using the Move option on the dropdown list of the floating pane. The cursor should automatically change to NSWE cursor which you can the move to the right edge of the excel application.
As the cursor hits the edge the pane should snap back to being attached to the right edge