Question: In Lubuntu distribution of Ubuntu 18.04.1 LTS, I try to set the background of the terminal with some transparency but it takes no effect.

I'm using LXterminal, which come with the distribution

[![Setting transparency](https://i.stack.imgur.com/pFgeL.png)](https://i.stack.imgur.com/pFgeL.png)

Is it anything of the new Lubuntu?

Answer: 
I couldn't find the transparency option either in lxterminal 0.3.1. Looks like they dropped it at some point. See <https://sourceforge.net/p/lxde/bugs/910/>. From there:

> 
> Was due to a configure variable. Passing --enable-gtk3 to ./configure of any recent version (tested 0.3.1 sourceforge and git latest on "master") breaks faux transparency. So the gtk3 version of lxterminal seems to not support faux transparency.
> 
> 
> 

In any case, what this terminal had in the past was "fake transparency" also known as [pseudo-transparency](https://en.wikipedia.org/wiki/Pseudo-transparency). You could only see through to the root window's wallpaper even if there's another application's window between your terminal and the root window. From the wikipedia entry:

> 
> This pseudo-transparency, so called as the background pixmap of the root window is visible (analogous to desktop wallpaper) rather than any obscured windows, allows users to make windows look less imposing (such as Terminal emulators, which usually comprise large chunks of text), and to integrate the appearance of windows with their desktop themes.
> 
> 
> 

If you want true transparency, you can install Compton by running `sudo apt install compton`.

Once that's installed, create `~/.config/compton.conf` as a **plain** text file.

Add the following content:

```
inactive-opacity = 1.0;
inactive-dim = 0.2;
mark-ovredir-focused = true;
opacity-rule = [ "80:class_g = 'Lxterminal'" ];
shadow = false;
no-dnd-shadow = true;
no-dock-shadow = true;
blur-background = false;

```

and save the file. Then, via the menu, open `Preferences` > `Default applications for LXSession`.

In there, click on the tab for `Autostart` and paste in

```
compton --config /home/dkb/.config/compton.conf -b

```

making sure to change `dkb`, which is my username, to yours.

[![Autostart](https://i.stack.imgur.com/9BnjN.png)](https://i.stack.imgur.com/9BnjN.png)

Log out and then log back in again.

Now when you run `lxterminal`, you'll have true transparency: you'll see through to windows immediately below the terminal and your wallpaper if that's visible.

You can change the value in the opacity rule from `80` in your `compton.conf` to suit your tastes: the lower, the more transparent your terminal will be.

[![lxterminal with transparency](https://i.stack.imgur.com/txVA0.png)](https://i.stack.imgur.com/txVA0.png)

Please note that my `compton.conf` is rather minimal so as not to consume more resources. Of course, you can change settings to have a lot of fancy effects :) See <https://github.com/chjj/compton/blob/master/compton.sample.conf> for more.
In **Lubuntu 18.10** you just have to go to :

*Preference > LXQT settings > Session Settings*

Now Check the Compton(X Compositor) 
and Hit The Start Button

That's it now the Transparency option in terminal preference will work.