When comparing i3 vs LXQT, the Slant community recommends i3 for most people. In the question“What is the best edition of Manjaro Linux?” i3 is ranked 3rd while LXQT is ranked 6th. The most important reason people chose i3 is:
One of the biggest attractions of i3 is that it can be configured just about any way the user likes. Ranging from custom keyboard shortcuts to placement of opened apps, it is up to the user as to how they would like their window manager to behave.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Fully configurable (including tiling)
One of the biggest attractions of i3 is that it can be configured just about any way the user likes. Ranging from custom keyboard shortcuts to placement of opened apps, it is up to the user as to how they would like their window manager to behave.
Pro Windows can be turned into Tabs
i3 permits tabbing through windows by turning on Tab mode with $mod+w.
This shortcut can be changed in config file.
Pro Easily switch to and manage floating windows
i3 can allow for the user to manage floating windows. Floating mode can be toggled by pressing $mod+Shift+Space. This way the user can take advantage of tiling as well as floating windows, all in the same session.
Pro Excellent documentation
Every feature is thoroughly documented (including examples), and documentation is kept up-to-date. For questions that are not answered by the i3 user guide, because they concern tools outside of i3 for example, there is the community question & answer site.
Pro Can stack
i3 allows for stacking of windows in its environment.
Pro Fast, especially on weaker hardware
Tiling means there are no fancy compositing or window effects to take up system resources.
Pro Never have to take hands off keyboard
Keyboard shortcut based navigation can seem daunting at first, but one quickly gets used to it. It enables the user to never have to take their hands off the keyboard, meaning that they can use their computer quickly and efficiently.
Pro No window borders
Screen area is not wasted by window decorations. This allows programs to use the entire screen.
NOTE: Default config has window title bar enabled so there is a little screen space lose on the top of the screen.
Pro Simple to use
Configuration is nearly automatic and simple, which can be really helpful to beginners.
Pro RandR support
RandR provides more information about your outputs and connected screens than Xinerama does. To be specific, the code which handled on-the-fly screen reconfiguration (meaning without restarting the X server) was a very messy heuristic approach and most of the time did not work correctly — that is just not possible with the limited information that Xinerama offers (just a list of screen resolutions and no identifiers for the screens or any additional information). Xinerama simply was not designed for dynamic configuration.
Pro Easily readable plain-text configuration
i3 has plain-text configuration, meaning that no lua or haskell is needed. This makes it rather easy to recommend i3 to other people without worrying whether or not they have the knowledge to configure it as it can be read by anyone without prior knowledge.
Pro VIM Style key bindings
You can configure i3 so that your keys for moving windows is similar to vim, for example, M-j to move the window down.
Pro Terminal bell can be used to notify of completed actions
Terminal-bell gets passed through and marks the workspace visibly.
Pro Sane development process
i3 uses test driven development with an extensive test suite to prevent bugs from ever happening again. All external contributions require a thorough code review to guarantee a certain level of quality.
Pro Can be reloaded quickly and configured without a client restart
Just two hot keys: Shift+Super+C to reload the config and Shift+Super+R to restart (which takes less than one second). Restarts pick up new versions of i3 or the updated config file, so you can upgrade to a newer version or quickly see the changes to i3 without quitting your X session.
Pro Layouts can be saved and reused
Pro Configuration allows for multi-monitor support
User can assign specific workspaces to specific displays as well as apps to workspaces. This makes possible opening set of most used apps with 1 shortcut always on the same screens.
Pro Great choice for keyboard users
The user keeps their hands in one spot (most of the time). One will find that the mouse is used less and less, making navigation quicker over time.
Pro Modular
By taking advantage of the modular KDE Frameworks, LXQT is able to offer a modular architecture that allows the user to easily swap components.
Pro Lightweight emphasis
With a focus on being "light-weight", it is to KDE Plasma what XFCE is to GNOME: a familiar enough looking lighter alternative to the more fully featured environment that may work better on lower-end devices and for people who want as lean a system as possible.
Pro Beautiful GUI using Qt.
Pro Great for old and low-end devices
LXQt is unparalleled in its ability to run on the weakest of machines without a problem.
Pro Utilizes Qt
As the name suggests, LXQt takes advantage of the Qt ecosystem to provide a beautiful and performant user experience.
Pro Doesn't use GTK3
Pro Doesn't use GTK3
Cons
Con Missing "include" possibility in config
While pretty good and easy to use for common tasks, the configuration language is missing the include
directive common in other languages. You can use a workaround - a shell script to config parts on demand. It would be best if this were built-in however.
Con Poor floating window support
Sometimes this is necessary, even when the Dev rejects feature requests. Firefox child windows (option dialog) is an example.
Con Not as configurable as other WMs
Unlike XMonad or Awesome, i3 can't be configured in a turing complete language, so it is much harder to alter its core functionality to do exactly what the user wants.
Con Manual tiling
The layout isn't automatic. The user must move panels manually and may indeed end up spending time on that rather than on working with the application.
Con No shortcut to switch between two recently used applications/windows
You can easily switch between two workspaces but not two windows (which are not adjacent to each other). The functionality simply isn't there and the dev refuses to include it as a part of i3 core. This can get annoying when you have multiple windows in the same workspace. There is a manual workaround though.
Con Steep learning curve
Has a steep learning curve for beginners.
Con Cannot share workspaces between monitors
You have to pick and choose which workspaces go where, which effectively halves the number of workspaces you have. The developer refuses to allow this feature.
Con It has some issues with transparency
Using transparent windows can cause them to crash.
Con The plain-text configuration may not be suitable for beginners
i3 is configured through a plaintext configuration file. While it's very powerful and easy to learn, it may not be entirely user-friendly for those who have never edited a text configuration.
Con A program running on Discrete GPU may have problem rendering
That is a common issue with laptops which renders some programs in discrete GPU but passes the frames through integrated GPU to display. This makes it pain to play games on laptops using discrete GPU.
Con Documentation is online
Can't access it offline unless you download the page.
Con Poor file manager
pcmanfm-qt is lightyears behind its GTK version.
Con Very limited in customization
Very few themes available, especially modern themes.
Con Ugly
Con Multiple application sources
Which leads to an inconsistent desktop.
Con Not a full desktop environment
Like LXDE or Xfce it is not a full desktop envirnment and is missing many utilities that need to be borrowed from other desktops which will bloat the desktop.
Con UHD screens hardly supported
DPI settings are not adopted. The readability, usability of this DE on UHD screens is not advisable. Fonts are not scaled at all.
Con Unthemeable for usual users
As all Qt desktop environments themeing is hard since you need to know C++ , there is a sideway using qss however its not as powerful as GTK, Enlightenment or Windows theming.
Con Depends too much on KDE
Even the programs/apps shipped with LXQt are from the KDE project. They don't have their own projects yet.
It's pretty similar to Budgie that depends on Gnome for almost everything.
Con Pcmanfm-qt needs gvfs
you can mount drives with mount, but pcmanfm uses gnomes gvfs to mount drives.
Con Missing Features = Lightweight
For the LXQT developers, lightweight is a synonym for missing features.
Con A lot of bugs
This is a very disappointing desktop environment, it's very buggy. Although there still is hope that these issues will be resolved.
Con Not quite ready for open deployment
In the current state, LXQT is a beta desktop that feels like a heavy alpha. A lot of the tools and underlying features are in a testing state, while the LXQT project itself has not had a gold (1.0.0) release as of yet.