Libre Office Writer: Docking Navigator on RHS - defaults to LHS when Writer is next started

I have LIbre Office Writer 25.2.0.3 (x64) installed on two PCs: one is Windows 7 and the other is Windows 10.

On the Win 10 PC, I have docked the Navigator bar on the RHS of the window (ie right of document) and this positioning is remembered every time I start Writer.

On the Win 7 PC, the Naviagator was a floating window which then defaulted to LHS when I did Ctrl-Shft-F10. After a lot of experimentation I was able to drag the Navigator to the RHS and get it to dock there.

But… As soon as I close Writer and restart it, it defaults to LHS. So it is remembering that I want it docked rather than free-floating, but defaults to the wrong side.

Is there something I’m doing wrong?

Here are screenshots of the default LHS position and the temporary but not persistent RHS position.

Navigator in default LHS position
Navigator in temporary, not persistent position