Comment 26 for bug 1288655

@martin-weinberg-5 I tried the dconf write as you suggested, and I did alt-F2 and "r" to restart Gnome, but it doesn't seem to have changed anything.

***As I wrote the above, I remembered that I'd left some terminal windows open during the process. I've re-tested but closed all windows before restarting Gnome and it *does* resolve the problem. However, I now have a menu bar on all my terminal windows. (screen grab attached for the benefit of others).

For the moment, I'll reset that entry:
dconf reset /org/gnome/terminal/legacy/headerbar

..but hopefully that will help a little in figuring out where the underlying bug is.