Several days ago I noticed that "Hide bookmarks toolbar" option is missing, I used to use this option when I right click at the top of the Firefox window. Then I tried to hide it by clicking on View -> Toolbars and then I should uncheck the Bookmarks toolbar but it's missing here too. When I click on Customize I used to see Bookmarks toolbar at the bottom of the page under Toolbars menu item, but I can't see it here too.
I tried restarting without addons and I also refreshed the Firefox, didn't help.
This question is originally posted on Firefox support so I'll paste the link in case someone needs some info: https://support.mozilla.org/en-US/questions/1209543
I've been facing the same problem (no more bookmark toolbar and no option to enable it by right-clicking on the main toolbar like there used to be). Thought of a problem with the new version (as the problem occurred after last update for me) but my wife found a way to enable the bookmark toolbar.
You need to add the bookmark item to the main toolbar, click on it, select "Bookmarks toolbar" ("Barre personnelle" in French, could be a slightly different label), then check "Display the bookmarks toolbar".
See here what I'm talking about (in French):