tabs in Midori missing

I had this problem before upgrading from Lubuntu 14.04.4 to 16.04.1. Basically, there is a bug concerning the tabs bar: it's missing. It disappeared one day and it's not there anymore. I can activate the lateral tab panel, but it takes a lot of space on the screen, so it's not really useful. Thanks.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: midori 0.5.11-ds1-2
ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13
Uname: Linux 4.4.0-31-generic i686
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: i386
CurrentDesktop: LXDE
Date: Sun Jul 31 01:30:07 2016
InstallationDate: Installed on 2015-09-13 (321 days ago)
InstallationMedia: Lubuntu 14.04.1 LTS "Trusty Tahr" - Release i386 (20140722.2)
ProcEnviron:
 LANGUAGE=es_ES
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=es_ES.UTF-8
 SHELL=/bin/bash
SourcePackage: midori
UpgradeStatus: Upgraded to xenial on 2016-07-30 (0 days ago)