In Sierra 10.12.2, Libreoffice opens every windows (document window or function windows such as goal seek) in a tab as if it were in FullScreen mode. This makes it unusable. The tabs can be detached by dragging from the title bar but its size corresponds to the main window which is terrible when it is a function, such as goal seek or a menu option as Preferences.
*** This bug has been marked as a duplicate of bug 103486 ***