In early 2014, two lightweight desktop projects — LXDE and Razor-Qt — merged to form LXQt, a Qt-based desktop environment designed to be fast, modular, and easy on system resources. Version 0.7.0 was the first release to reach a wider audience, and if you were running Ubuntu 14.04 LTS Trusty Tahr, you could install it through a community PPA and get an early look at what would eventually become the default desktop for Lubuntu. This guide covers the installation process, first-run setup, what to expect from this early release, and how it compares to the LXDE desktop it was designed to replace. We have tested this on both stock Ubuntu 14.04 and Linux Mint 17 (which shares the same package base), and the process is identical. If package management from the terminal is new to you, our CLI Basics page covers the essentials.
Background: The LXDE + Razor-Qt Merger
LXDE had been the go-to choice for lightweight Linux desktops since the late 2000s. Written in GTK+ 2, it was fast and simple, but by 2013 it faced a problem: GTK+ 2 was being deprecated in favour of GTK+ 3, and porting LXDE to GTK+ 3 would have required rewriting large portions of the codebase. Meanwhile, Razor-Qt was a young project pursuing the same lightweight desktop idea but built on Qt — a toolkit with strong backward compatibility and a cleaner API for the kind of modular desktop components both projects wanted to build.
The merger was announced in mid-2013. Rather than porting LXDE to GTK+ 3, the LXDE developers joined forces with the Razor-Qt team to build a new desktop on Qt. The result was LXQt — inheriting LXDE’s philosophy and user-facing design language, but with a completely different toolkit underneath. Version 0.7.0, released in May 2014, was the first post-merger release to carry the LXQt name and a reasonably complete set of components.
What You Get with LXQt 0.7.0
The 0.7.0 release included a core set of desktop components:
- lxqt-panel — a bottom panel with application menu, task manager, system tray, and clock. Functionally similar to lxpanel from LXDE but rewritten in Qt.
- PCManFM-Qt — a Qt port of the PCManFM file manager. In this release it handled basic file operations, but features like tabbed browsing and built-in terminal embedding were still being polished.
- lxqt-runner — a quick-launch dialog (think Alt+F2) for running commands or launching applications by name.
- lxqt-config — a unified settings center for configuring appearance, keyboard shortcuts, monitor settings, and session options.
- Openbox — LXQt used Openbox as its window manager, same as LXDE. This was not a new component, just a shared dependency.
Step-by-Step Installation
Step 1: Add the LXQt PPA
The LXQt packages were not included in Ubuntu 14.04’s official repositories. A community-maintained PPA provided them:
sudo add-apt-repository ppa:lubuntu-dev/lubuntu-daily
Press Enter to confirm. This PPA was maintained by the Lubuntu development team, who were actively evaluating LXQt for future Lubuntu releases.
Note: Some guides from the era referenced
ppa:lxqt/testinginstead. Both carried LXQt 0.7.0 packages for Trusty, but the Lubuntu daily PPA was generally more up to date with bug fixes.
Step 2: Update Package Lists
sudo apt-get update
Watch for any errors in the output. If the PPA key was not imported automatically, you will see a GPG warning — resolve it with:
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys <KEY_ID>
Step 3: Install LXQt
sudo apt-get install lxqt-metapackage
This pulls in the full LXQt desktop: panel, session manager, file manager, configuration tools, Openbox, and the default theme. The download is modest — roughly 60–80 MB of packages depending on what Qt libraries you already have installed. If you are on a stock Ubuntu install with Unity, Qt is not present and the download will be larger (around 150 MB) to pull in the Qt 5 base.
Alternatively, for a minimal install without recommended extras:
sudo apt-get install lxqt-metapackage --no-install-recommends
Step 4: Choose LXQt at the Login Screen
After installation, log out of your current session. At the LightDM login screen, click the session selector icon (usually a small desktop icon near the username field) and choose LXQt Desktop. Enter your password and log in.
Step 5: First-Run Configuration
On first login, LXQt starts with a default Openbox configuration and its own panel at the bottom of the screen. A few things to configure immediately:
Panel position and size. Right-click the panel and select “Configure Panel” to adjust height, position (top or bottom), and auto-hide behaviour.
Application menu. The main menu in the panel uses freedesktop.org .desktop files, so all your existing applications should appear. If some are missing, they may need their .desktop files updated to use recognized categories.
Appearance. Open LXQt Configuration Center (from the menu or by running lxqt-config) and navigate to Appearance. You can set the Qt widget style, icon theme, and font. LXQt 0.7.0 shipped with a limited set of built-in themes, but it respected any Qt 5 theme installed on the system.
Openbox settings. Window decorations, keyboard shortcuts for window management, and virtual desktop configuration are handled by Openbox. Run obconf (install it with sudo apt-get install obconf if not present) to configure these.
How LXQt 0.7.0 Compares to LXDE
The most obvious difference is visual — Qt widgets render differently from GTK+ 2 widgets, and application themes do not cross over. If you had a carefully themed LXDE desktop with a GTK+ 2 theme, LXQt will look different even with effort spent on configuration. The Qt ecosystem has its own theme engines.
Performance-wise, LXQt 0.7.0 was slightly heavier than LXDE at idle — roughly 30–40 MB more RAM — due to Qt library overhead. In practice, on any machine with 512 MB or more of RAM, this difference was imperceptible. Both desktops were dramatically lighter than Unity, GNOME Shell, or KDE Plasma.
Feature parity was the bigger gap. PCManFM-Qt in 0.7.0 lacked some features its GTK counterpart had refined over years — drag-and-drop to the desktop was inconsistent, and the sidebar bookmarks occasionally did not sync with GTK bookmark files. The panel was functional but had fewer plugins available than lxpanel. These were early-release growing pains, and subsequent LXQt releases (0.8, 0.9, and the 0.14+ series that shipped with Lubuntu 18.10 and beyond) closed these gaps.
Common Pitfalls
Qt and GTK theme mismatch. GTK applications running under LXQt use GTK+ 2 or GTK+ 3 theming, not the Qt theme. This means Firefox, GIMP, and other GTK apps may look visually inconsistent. Install lxqt-config-appearance (if not already present) and configure the GTK theme under its “GTK Style” tab to choose a GTK theme that visually complements your Qt theme.
Missing system tray icons. LXQt 0.7.0’s system tray implementation had some compatibility issues with applications that used the older XEMBED tray protocol versus the newer StatusNotifierItem protocol. If an application’s tray icon does not appear, try restarting the application after the panel has fully loaded.
Screen resolution not saved. The LXQt monitor configuration tool in 0.7.0 was minimal. If your display resolution reverts after reboot, create an xrandr script and add it to LXQt’s autostart: place a .desktop file in ~/.config/autostart/ that runs your xrandr command at login.
Openbox compositing. LXQt does not include its own compositor. If you want transparency, shadows, or tear-free rendering, you need to run a standalone compositor like compton (now called picom). Install it and add it to autostart:
sudo apt-get install compton
Create ~/.config/autostart/compton.desktop with Exec=compton -b to start it at login.
File associations may default incorrectly. Because PCManFM-Qt and PCManFM (GTK) use slightly different MIME handling, double-clicking files in the file manager may open unexpected applications. Check and update MIME associations in LXQt Configuration Center > File Associations.
The Road from 0.7.0 to Lubuntu’s Default
LXQt 0.7.0 was very much a “version one” release — functional, fast, and promising, but missing the polish that daily-driver users expected. The project iterated quickly through 0.8 and 0.9 over the next year, and by the time Lubuntu officially adopted LXQt as its default desktop in 2018 (Lubuntu 18.10), the environment was in the 0.13–0.14 range and dramatically more refined. If you tried 0.7.0 and found it rough around the edges, the modern LXQt experience in current Lubuntu releases is worth revisiting — it kept the lightweight philosophy while gaining the fit and finish that the early releases were still building.