Edit menu missing when visiting site as admin

That little black edit menu along the top of my site which appears when I’m logged in as admin is suddenly missing. I’ve deactivated all plugins, switched to twentytwelve menu and logged in and out as different users, but the menu doesn’t reappear. The only way for me to go back and forth from backend to frontend is to dial up the webpage manually and add the suffix wp-admin.

Any ideas? Searched for similar posts and tried all solutions that seemed to apply.