Have you always installed libreoffice from apt?
If you have ever installed from the libreoffice.org deb files (maybe a long time ago), check that you don't have two versions installed and the symlinks are all good.
Results from using the window menu, new user:
[app] (name=libreoffice) (class=libreoffice-writer)
[Position] (UPPERLEFT) {6% 7%}
[Shaded] {no}
[Deco] {NORMAL}
[Sticky] {no}
[Minimized] {no}
[Maximized] {yes}
[Fullscreen] {no}
[Layer] {8}
[Alpha] {255}
[end]
[app] (name=libreoffice) (class=libreoffice-calc)
[Shaded] {no}
[Deco] {NORMAL}
[Sticky] {no}
[Minimized] {no}
[Maximized] {yes}
[Fullscreen] {no}
[Layer] {8}
[Alpha] {255}
[end]