Archisman Panigrahi's questions

I am a developer of Safe Eyes (an app that reminds you to blink eyes to prevent eye strain), and someone requested a feature that they want to open the app in Spanish, while the system language for all other apps is set to be English.

The app has already been translated to many languages, and would change its language if the system language is changed to Spanish.

When the Spanish language pack is already installed, is there any way the app can be launched in a Spanish while the system language is still English? Maybe with some environment variable while running the app?

In case you need to test the app to provide an answer, you can use the official PPA in Ubuntu 24.04 (or use the package from official repositories on previous versions of Ubuntu), as the official repository version in broken in 24.04:

sudo add-apt-repository ppa:safeeyes-team/safeeyes

And sudo apt install safeeyes

I am writing a bash script to set up the all the software I need after installing Ubuntu. If the computer is a laptop, I want to install tlp for power management. If it is a desktop, tlp is not necessary.

Is there a command with which I can figure out whether the computer is a desktop or a laptop/tablet?

Perhaps, detecting the presence of a battery is the signature I should look for.

Previous versions of Ubuntu (more than ten years ago) seemed to have more effects than currently present in Cheese.

Is there any way to add more effects in cheese?

I am unable to install a .deb package downloaded from the internet.

In previous versions of Ubuntu, the software center would act as the GUI frontend to install deb packages but the new snap store does not support installation of deb package.

How do I install .deb package like Google Chrome or Zoom in Ubuntu 24.04 using GUI?

I use the Julia programming language on a Chromebook with only 32 GB internal storage.

The .julia directory in the home folder consumes several gigabytes of space. This directory contains all the julia packages (similar to python libraries), and it is essential for Julia to use those packages.

I have a microSD card with a lot of free space. How do I move the .julia directory to the microSD card?

I am using Kubuntu 23.04.

I came across this question about Google Keep. The existing answer is no longer relevant, since Chrome apps are being phased out.

How to use Google Keep with Ubuntu 22.04?

In recent releases of Ubuntu, adding a PPA automatically updates the package cache immediately.

Sometimes, I need to add several PPAs (e.g. after a new installation), and would like to manually run apt update in one go, after adding all the PPAs.

How to do that?

I found this question, which suggests using add-apt-repository -n ppa:user/repo.

How to change the default behavior so that the package cache will not be updated even when the -n flag is not supplied?

For example, in Linux Mint, the package cache is never automatically updated after adding a PPA. How to make that the default behavior in Ubuntu?

I have a pdf (having multiple pages) containing some colorful certificates, and need a black and white (grayscale) version of it.

Is there any way to make it grayscale with a single command, or with any simple GUI program (preferably FOSS)?

In principle, I can open all the pages separately in GIMP, make them grayscale, and rejoin, but that would take a lot of effort.

Cutefish is a new desktop environment that resembles the Mac OS UI. It was recently featured in OMG! Ubuntu!.

^{image source: The OMG! Ubuntu! article}

Cutefish OS is Debian based, so the desktop environment may be installed in Ubuntu without too much hassle.

How to install the Cutefish DE in Ubuntu, let's say in the latest Ubuntu 21.04?

Suppose I turn off swap, and all RAM gets used up. What will happen?

Will the machine freeze? Will Ubuntu (or the Linux kernel) intelligently close the programs consuming too much memory?

Background: I have an old desktop with 3 GB RAM, which works smoothly with Xubuntu 20.04. When I open many tabs in Firefox and some large PDF files simultaneously, about 2.4-2.5 GB RAM is utilized, and about 700-800 MB of swap space is used. However the desktop interface becomes somewhat slow to respond, and sometimes becomes unresponsive while loading RAM -> swap.

It again becomes responsive when I close some of these softwares and run the command sudo swapoff -a && sudo swapon -a, so that the content of swap is loaded back into RAM.

I found that the system does not become slow to respond when swap is turned off before opening such programs (I was careful so not to consume all the RAM).

I want to know whether there can be any severe issue if I turn off the swap permanently and all RAM is used up. Of course, I would try to ensure that it does not happen. However, I would prefer to use a faster system (while being careful not to open too many programs simultaneosly), rather than using a slower system with a larger effective memory (physical RAM + swap).

xrandr can be used to change the display brightness using the command line. For example,

xrandr --output VGA-1 --brightness 0.4

Wayland does not support xrandr. Is there any similar tool in Wayland that can be used to control brightness and color temperature?

Note: This is NOT a duplicate of this question because that is about changing resolution, I want to control brightness on a desktop computer that does not support sys/class/backlight, so that frontends like Brightness Controller or Redshift can be made to work with Wayland.

I need to fill up a pdf with XFA forms. Okular says that or does not support XFA forms.

Xreader displays the following message and asks to install Adobe Reader.

If this message is not eventually replaced by the proper contents of the document, your PDF
viewer may not be able to display this type of document.

Is there pdf reader (not a pdf editor which actually draws on the document) in Ubuntu that supports XFA forms?

This is not a duplicate of Is there software that can fill PDF forms? because answers in that question do not address XFA forms (as mentioned in some comments).

In desktop environments like Unity, Cinnamon, MATE, the combination Ctrl+Alt+←/→ changes the workspace.

How to assign custom keyboard shortcuts in kde plasma 5 to change workspaces (i.e. virtual desktops)?

In recent versions of Ubuntu and in some computers, Cheese keeps saying:

There was an error playing video from the webcam

A bug was reported in Launchpad, which has not been solved.

The external webcam in my system is Logitech C170.

In Unity dash GIMP 2.8.10 has a icon and uses a different one in launcher.

GIMP in Dash

GIMP in Launcher

I searched for GIMP in "File System" and got this.

How can this be done while packaging other apps?

I had Xubuntu 14.04 beta 1 installed. Now I have installed ubuntu-desktop package but I see that there are still Xubuntu application icons, login screen, theme, boot screen etc.

How to completely remove them and configure the default Ubuntu things?

Will sudo apt-get remove xubuntu-desktop and sudo apt-get autoremove do?

I noticed that Ubuntu SDK recently had some updates and it installed a program named "Click". I would like to know what they are and how to use them.

Also, would they make Debian packaging easier?

Is it possible? A PNG usually consumes less storage space compared to an SVG. Sometimes I need small sized images in sites like Launchpad.

When I simply save as PNG, the background remains white, not transparent.

I submitted my app "Brightness Controller" under proprietary license and it has been published. It contains an executable .py file. But the app depends on python-wxgtk2.8 I wrote it in the comments field but probably the packagers have ignored it. Is there any way I can add the dependency myself?
Please note that I had not debianized the package. I just tarred the brightness.py file and submitted it. Can I just make a .deb with the dependency file and submit it?
The app is originally open-source, but I submitted it under proprietary so that I won't have to package it.

We have made a .py file that controls brightness of the screen. It has a GUI with slider for controlling and runs when it is double clicked after marking it as executable.

But we want to make a .deb package with it for easily distributing. Is there any way to do it with Quickly? If not, then what are the other ways?

We also want to associate it with an icon.

The project we are trying to debianize is here.