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Archives For November 30, 1999

GNOME 41 Released! New Remote Desktop App, Multitasking & Mobile Network Settings

Last updated: September 23, 2021

After half a year of development, the GNOME project announced version 41 of its popular Linux desktop environment.

GNOME 41 comes with some exciting new features. The upper right corner system tray menu now includes option to make it easy to switch Power Mode between “Balanced” and “Power Saver”. It’s said that “Performance mode” is only visible on hardware that supports this feature, though I don’t understand which hardware required, may be a dedicated graphics card.

The GNOME Settings panel introduced two new items in the left pane: Multitasking and Mobile Network.

The “Multitasking” pane offers options to toggle top-left hot-corner to open Activities overview, app window auto-resizing function when dragging against screen edges; set dynamic or fixed number of workspaces; show workspace on primary only or all displays; super + tab switching for apps on all workspaces or current workspace only.

The “Mobile Network” pane is only visible when a supported modem is present, e.g., 2G, 3G, 4G, and GSM/LTE. It allows to set the network type, whether to use mobile data and data roaming. And it supports multiple SIMs and modems, allows to easy switching network modes.

Other changes in Gnome 41 include:

  • New “Connections” remote desktop app with VNC and RDP support.
  • Overhaul Gnome Software.
  • Redesigned Gnome Music.
  • Faster response to keyboard & pointer input on Wayland.
  • New default GL renderer for GTK4.
  • Create encrypted .zip archives in Files.
  • Import events to Calendar from .ics files.
  • Code cleanup in Mutter, and more.

How to Get Gnome 41:

Usually, the newest GNOME desktop will be first made into Fedora and Arch Linux. Users are recommended to wait your Linux distribution to include the desktop environment.

For testing and development purpose, you can try the GNOME OS either in virtual machine or real computer. Or download the iso image from the link button below:

Download GNOME 41
In News
 

gThumb 3.12.0 Released! How to Install via PPA in Ubuntu 20.04

Last updated: September 20, 2021

gThumb image viewer and organizer announced version 3.12.0 as the new stable release series!

gThumb 3.12.0 is the new stable series since the last 3.10.x, while the 3.11.x is the development release.

What’s New in gThumb 3.12.0:

The new release includes many new features compare to the previous stable 3.10.x. They are all introduced in the 3.11 development releases, so you may already enjoy using them for a period of time.

With libheif library, gThumb now opens AVIF, HEIF (include Apple’s HEIC) images, and allows to save images as AVIF. And it supports JPEG XL images using the jpeg-xl library. A template editor is available to edit text values with special codes, for use in script commands, rename templates, print header and footer, etc.

Besides that, it improved file navigation for directory contains thousands of images. The file list now starts more thumbnailers in parallel, status bar has button to show the progress dialog. And the color picker tool shows colors in two more formats: rgb in % and hsl. Others include:

  • Allow to set shortcuts to activate filters.
  • Allow to mount unmounted volumes.
  • Add file actions to the viewer context menu.
  • Read color profiles from png files as well.
  • Option to show/hide the status bar.

For those already running gThumb 3.11.4, there are only bug-fixes and translation updates.

How to Install gThumb 3.12.0 in Ubuntu:

The software does not provide official binary package. Besides building from the source tarball, you may install it via the unofficial Ubuntu PPA.

1. Add the Ubuntu PPA.

The PPA so far provides packages for Ubuntu 20.04, Ubuntu 21.04, Ubuntu 21.10, and Linux Mint 20. It contains package for Ubuntu 18.04 but lacks JPEG XL support.

Firstly open terminal either from start menu or by pressing Ctrl+Alt+T on keyboard. When it opens, paste the command below into terminal and hit run:

sudo add-apt-repository ppa:ubuntuhandbook1/apps

2. Update system package cache.

Adding PPA will automatically refresh the package cache in Ubuntu 20.04 and higher. However old versions and some Ubuntu based systems does not. To do it manually, simply run command in terminal:

sudo apt update

3. Install / Upgrade gThumb.

Finally, either run the apt install command in a terminal window to install the image viewer:

sudo apt install gthumb

Or use the Software Updater (Update Manager) utility to receive package updates. Un-check other packages from the PPA if you don’t want them.

Uninstall / Restore gThumb:

You can restore to the stock version of the image viewer and organizer by purging the PPA repository. To do so, simply run command:

sudo apt install ppa-purge && sudo ppa-purge ppa:ubuntuhandbook1/apps

You may also keep the gThumb package but remove the Ubuntu PPA, since it contains many other software packages that you don’t prefer. To do so, either run command in terminal:

sudo add-apt-repository --remove ppa:ubuntuhandbook1/apps

Or remove the repository line under ‘Other Software’ tab via Software & Updates utility.

In Howtos, News
 

GIMP 2.10.28 Released! How to Install via PPA in Ubuntu 20.04

Last updated: September 19, 2021

GIMP announced the 2.10.28 release of the popular image editor. The release includes mainly bug-fixes and stability improvements.

The source tarball of version 2.10.26 is available to download 2 weeks ago. Due to a build bug, the project team skipped it and announced GIMP 2.10.28 as the latest stable release with fixes.

Changes in GIMP 2.10.28:

For Windows users, the new GIMP released fixed some long standing issues, including:

  • Fixed very slow file dialogs that happen on slow or unavailable network devices, removable devices connection, or even fake floppy drives.
  • Fixed crash when opening files in specific third-party software.
  • GTK outputting the wrong character on some keyboard input using Input Engines.
  • TIFF exporting locks the TIFF files due to bug of Windows thumbnailer.
  • GIMP prevent some apps to open, when they need to watch some specific directory.
  • Apps with invisible windows, e.g., e.g. gesture shortcuts, screen capture, used to interfere and break some mouse interactions.

For macOS Big Sur, GIMP applied performance improvements to the packages since version 2.10.22 as experiments. Now the code has been moved to the main codebase.

The release also features GEGL 0.4.32, which introduced new edge_handling parameter allows to choose whether areas outside the input to be treated as above or below threshold for calculating distance. And the test system gets some nice improvements.

Other changes in GIMP 2.10.28 include:

  • The Dashboard dockable now has memory support in OpenBSD.
  • Fixes to plugins, including C-source, DICOM, GIF, PS, Sunras, BMP, DDS, PSD, TIFF, Gimpressionist, metadata viewer and several script-fu scripts.
  • A new Script-Fu function (dir-make) enables to create directories from scripts.
  • Fixed some accessibility issues in themes.

How to Install GIMP 2.10.28 in Ubuntu:

1. GIMP Flatpak:

The project team recommends the flatpak package, the universal Linux package format runs in sandbox. The package is available at flathub.org. Users need to follow the setup guide and install the flatpak via the command in the bottom of the link page.

2. GIMP Snap:

The image editor is also available as Snap, another universal package format developed by Canonical, the company behind Ubuntu.

The snap version is so far GIMP 2.10.24. It however will automatically update to the latest (once published) after installed it. And the snap is available in Ubuntu Software:

3. Ubuntu PPA

For those stick to the classic .deb package, GIMP 2.10.28 is available to install via this unofficial PPA in Ubuntu 20.04, Ubuntu 21.04, and Ubuntu 21.10.

1.) Firstly, either search for and open terminal from the Activities overview screen, or press Ctrl+Alt+T on keyboard. When terminal opens, run command to add the PPA:

sudo add-apt-repository ppa:ubuntuhandbook1/gimp

Type user password (no visual feedback) when it asks and hit Enter to continue.

2.) Next, install GIMP 2.10.28 either by running apt command in terminal:

sudo apt install gimp gegl

or upgrade the editor using Software Updater (Update Manager):

Remove PPA and restore GIMP:

For any issue, you can purge the Ubuntu PPA which will downgrade the installed packages to the stock versions. To do so, firstly install the ppa-purge utility:

sudo apt install ppa-purge

Next run command to purge the Ubuntu PPA:

sudo ppa-purge ppa:ubuntuhandbook1/gimp
In Howtos
 

EasyEffects (Formerly PulseEffects) – Apply Audio Effects to PipeWire Apps

Last updated: July 18, 2023

The popular audio manipulation tool, PulseEffects, finally adds supports for PipeWire sound server by re-naming to EasyEffects.

EasyEffects is a GTK4 app designed for only PipeWire sound server. For PulseAudio, default sound service in current Ubuntu releases, PulseEffects is still available.

The UI looks almost same as before, and it may apply effects including Auto gain, Bass enhancer, Bass loudness, Compressor, Convolver, Crossfeed, Crystalizer, De-esser, Echo Canceller, Equalizer, Exciter, Expander, Filter, Gate, Limiter, Loudness, Maximizer, Multiband compressor, Multiband gate, Noise reduction, Pitch, Reverberation, Stereo tools.

Besides manipulating sound output, it may also apply effects to an input device, such as a microphone. This is, for example, useful in audio recording, but it also works well during voice conversations.

The PipeWire tab contains the options to select input & output devices, edit presets, and test signal.

How to Install EasyEffects in Ubuntu Linux:

The tool has been made into official repositories for Arch Linux, Gentoo, openSUSE and NixOS. Since Ubuntu sticks to PulseAudio, you install EasyEffects only when PipeWire is present as sound server (Read this tutorial for more).

UPDATE July 2023: For Ubuntu 23.04 +, EasyEffects has been made into the official repositories. So, either search for and install it from Ubuntu Software.

or press ‘Ctrl+Alt+T’ to open terminal and run command below to install it:

sudo apt install easyeffects

For Ubuntu 20.04 and Ubuntu 22.04, do following steps to install the app as Flatpak package:

1.) EasyEffects so far is only available as Flatpak package. Firstly, search for and open terminal either from the Activities overview screen or by pressing Ctrl+Alt+T on keyboard. When it opens, run command to install the flatpak daemon first if you don’t have it:

sudo apt install flatpak

2.) Next add the flathub.org repository, the place hosts a large amount of Flatpak apps by running command in terminal:

flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo

3.) Finally install EasyEffects flatpak package via command:

flatpak install flathub com.github.wwmm.easyeffects

If everything goes well, you may either launch it by searching for and opening from the overview screen, or run flatpak run com.github.wwmm.easyeffects command to start it from terminal.

Uninstall EasyEffects:

To remove the tool, open terminal, copy and paste the single command below and hit run:

flatpak uninstall --delete-data com.github.wwmm.easyeffects
In App Review
 

The Six Point Release Ubuntu 18.04.6 LTS is Out!

Last updated: September 17, 2021

The Ubuntu team announced the six point release for Ubuntu 18.04 today for the Desktop and Server.

Ubuntu 18.04.6 refreshed the disc images for the amd64 and arm64 architecture, re-enabling the usage on Secure Boot enabled systems due to the key revocation related to the BootHole vulnerability.

In August 2020, a set of security vulnerabilities in GRUB2 (the GRand Unified Bootloader version 2) collectively known as BootHole were disclosed. Today, another set of vulnerabilities in GRUB2 were disclosed, with similar implications.

See more in this blog post.

The release also includes many other security updates for additional high-impact bug fixes, with a focus on maintaining stability and compatibility with Ubuntu 18.04 LTS.

Download Ubuntu 18.04.6:

Ubuntu 18.04 has 5 year standard security support, and additional 5 year Extended Security Maintenance (esm) free for personal use.

To download Ubuntu 18.04.6, go the the link below:

Download Ubuntu

For Ubuntu 16.04 LTS, it’s able to upgrade to Ubuntu 18.04.6 using the Update Manger. See the documentation for more.

In News
 

Oracle Java 17 Released as New LTS, Here’s How to Install it in Ubuntu

Last updated: September 15, 2021

Oracle announced the release of Java 17 as the new Long-Term Support (LTS) release.

Java 17 LTS comes with thousands of performance, stability, and security updates, as well as 14 JEPs (JDK Enhancement Proposals). And Oracle will provide 8-year support for the release with security, performance, and bug-fix updates until 2029.

According to the release note, the next LTS will be Java 21 planned for September 2023, which changes the LTS release circle for every three years to two years.

What’s New in Oracle Java 17:

JDK 17 includes new language enhancements, updates to the libraries, support for new Apple computers, removals and deprecations of legacy features, and work to ensure Java code written today will continue working without change in future JDK versions. It also offers a language feature preview and incubating APIs to gather feedback from the Java community.

Updates in the release include:

  • Sealed classes and interfaces restrict which other classes or interfaces may extend or implement them.
  • Restore Always-Strict Floating-Point Semantics
  • New interface types and implementations for Pseudo-Random Number Generators (PRNGs), including jumpable PRNGs and an additional class of splittable PRNG algorithms (LXM).
  • Implement a Java 2D pipeline for macOS using the Apple Metal API.
  • New Arm 64-based Apple Silicon computers support.
  • Deprecate the Applet API for removal
  • Remove the Remote Method Invocation (RMI) Activation mechanism
  • Remove the Experimental AOT and JIT Compiler
  • Deprecate the Security Manager for removal
  • Strongly encapsulate all internal elements of the JDK, except for critical internal APIs such as sun.misc.Unsafe.
  • Pattern matching for switch expressions and statements, along with extensions to the language of patterns.
  • Improves Foreign Function and Memory API and Vector API.

How to Install Oracle Java 17 in Ubuntu:

Thanks to the “Linux Uprising” team ppa, an installer script has been created to automatically downloads and installs Oracle JDK 17 package, and sets Java 17 as the default Java version (setting JAVA_HOME, etc.) on 64-bit PC and arm64 devices, e.g., Rasperry Pi and Microsoft HoloLens 2.

1.) Firstly, open terminal either from system start menu or by pressing Ctrl+Alt+T on keyboard. When it opens, run command to add the PPA:

sudo add-apt-repository ppa:linuxuprising/java

Type user password when it asks (no asterisk feedback) and hit Enter to continue.

2.) Refresh system package cache. The PPA provides packages for Ubuntu 18.04, Ubuntu 20.04, Ubuntu 21.04, Ubuntu 21.10, as well as two old Ubuntu LTS (14.04 and 16.04). And old Ubuntu releases need to manually update system cache by running the command below in terminal:

sudo apt-get update

3.) Finally install the script package via command:

sudo apt-get install oracle-java17-installer

Once the script starts, it brings you to the screen for the license. Press Tab key on keyboard to select OK and hit Enter.

Then answer “Yes” via arrow keys and hit Enter to start downloading Java 17 package from oracle website.

Terminal will indicate the downloading and installing process for you. When everything’s done successfully, use java --version or javac --version command to verify the installation.

That’s all. Enjoy!

In News
 

Pika Backup is A Modern New Backup Utility for GNOME Desktop

Last updated: May 15, 2022

Looking for a personal data backup program? Pika Backup is a good choice for Ubuntu, Fedora, and other Linux with GNOME desktop.

Pika Backup is free open-source tool to backup your personal data into either local disk (e.g., an USB stick) or remote server using secure shell or sftp. It’s a modern GTK4 + libadwaita app that offers a stylish and easy to use user interface.

The utility is based on BorgBackup (aka Borg), features data de-duplication technique to save time and disk space since only changes are stored for daily backups. With the power of authenticated encryption technique, it also supports password protect for your data.

The app starts in a clean UI with a “Configure Backup” button to get started creating repositories to store backups. The top-left ‘+‘ icon is also present to do the same job.

Once click on “+” icon, it will ask you to create a new repository or select an existing repository to use in next dialog.

You may select to back your data into a remote server via ssh remote file transfer by specifying URL, e.g., “ssh://user@server.example.org/~/backup“, however borg need to be installed in the server side. For choice, the “sftp://” prefix can be used without borg.

Remote Location

Data can also be saved in local folder or removable devices, such as an USB drive. It will create a sub-folder in selected directory or device and save backup either encrypted or not depends on your selection.

After creation, it will recognize the USB repository automatically once you plug it in, allows you to either edit or select use the repository.

Local repository (USB Stick)

After creating / choosing the backup repository, it brings you to the file selecting screen. There you can choose any file folders, and exclude any for the backup. When you done data selection, click the green “Back Up Now” button to start. It indicates the process with how many percentage finished and how much time left.

setup backup

Backups are stored in unreadable files. You have to open the Pika Backup tool to mount the backups using “Browse saved files” under Archives tab. Then recover files or folder via opened file manager using copy & paste actions. This is not friendly in my opinion since no recover option present.

Archives tab to browser and manage your backups

Scheduled backups are not supported so far, and excluding files from a backup via regular expressions and alike is not implemented yet. Start in v0.4.0, it supports for schedule backup hourly, daily, weekly, or monthly with given time or day. It can also delete old archives automatically by keeping user selected number of last backups.

Install Pika Backup in Ubuntu Linux:

The Pika Backup software is available for most Linux via the universal Flatpak package.

Open terminal either via Ctrl+Alt+T keyboard shortcut or by searching for and opening it from ‘Activities’ overview screen. When it opens, run following commands one by one:

1.) Install flatpak daemon, if you don’t have it, by running command:

sudo apt install flatpak

For Ubuntu 18.04, users have to add the Flatpak PPA first.

2.) Next add the flathub repository, considered as official place hosts flatpak packages:

flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo

3.) Finally install the backup utility via this command:

flatpak install flathub org.gnome.World.PikaBackup

Like normal apps, you can search for and open it from ‘Activities’ overview screen.

Uninstall Pika Backup:

To remove the software, paste the command below into terminal and hit run:

flatpak uninstall --delete-data org.gnome.World.PikaBackup

And you may clear up unused run-time by running command:

flatpak uninstall --unused
In App Review
 

KeePass 2.49 Released! How to Install in Ubuntu 20.04 / 18.04

Last updated: September 11, 2021

KeePass Password Safe 2.49 released with user interface improvements and minor new features. Here’s how to install it in Ubuntu via PPA.

According to the release note, the new release added new dedicated context menus for custom string fields and auto-type associations in the entry dialog. Allows to copy names, values, target windows and sequences, copy and paste items, and do select all and move to actions. The button “More” is present to the right of the custom string fields and auto-type associations list to show the context menu.

The release also added optional “Auto-Type – Enabled” and “Auto-Type – Sequences” main entry list column. They are disabled by default and can be turned on via menu “View -> Configure Columns”.

KeePass 2.49 added support for importing Keeper 16.0.0 JSON files, and automatic screen reader detection based on the operating system’s screen reader parameter. Other changes include:

  • New ‘Show confirmation dialog when opening a database file whose minor format version is unknown’ option.
  • Dialog banners can now be read by screen readers
  • Added accessibility names for some controls
  • Controls in the accessibility/automation control tree are now ordered by their visual locations
  • Various accessibility enhancements and other improvements.

How to Install KeePass 2.49 in Ubuntu:

KeePass 2.x runs on Linux through Mono, the open-source .NET Framework-compatible software framework. The UI looks old. If you don’t like it, try KeePassX the native Linux password manager.

The software does not provide Linux binary package so far. Besides building from the source, you can use the unofficial Ubuntu PPA.

NOTE: I offer no warranty for any package in the PPA. Build rules and patches borrowed from the Julian Taylor’s PPA. Use it at your own risk.

1.) Firstly, open terminal from start menu and run command to add the PPA:

sudo add-apt-repository ppa:ubuntuhandbook1/keepass2

Type user password when it asks since sudo command need user authentication and hit Enter to continue

2.) Then run command to update package cache, though it’s done automatically in Ubuntu 20.04 & higher while adding PPA:

sudo apt update

3.) Finally install this mono based password manager package by running command:

sudo apt install keepass2

By keeping the Ubuntu PPA, next time a new release is published you’ll be able to upgrade it using system’s Software Updater (Update Manager) utility.

Uninstall KeePass2:

To remove the software package, run command in terminal:

sudo apt remove --autoremove keepass2

And remove the Ubuntu PPA either via command in temrinal:

sudo add-apt-repository --remove ppa:ubuntuhandbook1/keepass2

or by launching “Software & Updates” utility and removing the relevant line under “Other Software” tab.

In Howtos
 

YOGA Image Optimizer – Graphical Tool to Convert & Compress PNG, JPEG, WebP

Last updated: September 10, 2021

YOGA Image Optimizer is a graphical tool to batch convert photos into JPEG, PNG and WEBP, and compress file sizes while having equivalent quality.

It’s a free and open-source tool based on YOGA command line tool, which can also convert and optimize 3D models from various formats to glTF and GLB.

YOGA:

The YOGA backend uses Python Pillow library to convert images into PNG, JPEG, or WebP as you prefer. And it uses Google’s Guetzli library to generate JPEG that are typically 20-30% smaller than libjpeg while having some quality. Google’s Zopflipng and libwebp libraries are in use for optimizing other two image formats.

The command line tool also support converting and optimizing 3D models using the Open Asset Import Library (Assimp).

YOGA Image Optimizer:

The official front-end for YOGA provides an easy to use graphical interface to do converting and optimizing process in Linux and Windows.

Simply open a batch of photo images (press Shift or Ctrl while choosing files), it shows the thumbnails, input file name and size, as well as output name and file format.

Before you clicking “Optimize”, you can choose output format and set compress level for each or a selection of images.

YOGA Image Optimizer also features:

  • Multi-thread support. You can set how many CPU cores to use.
  • GTK theme support. It allows to choose between all installed GTK theme for the app only.
  • Dark Mode.
  • Custom output pattern.

Install YOGA Image Optimizer in Ubuntu Linux:

For Linux, the software can be installed either via universal Flatpak package or using pip (Python Package Installer).

1. Flatpak Package

Open terminal by pressing Ctrl+Alt+T on keyboard, you can then run following commands one by one to get the software via Flatpak in Ubuntu 20.04 and higher. For Ubuntu 18.04, you need to add this PPA before getting started.

a. ) Install the flatpak daemon if you don’t have it:

sudo apt install flatpak

b.) Add the Flathub the preferred repository hosting Flatpak package:

flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo

c.) Finally install the image converter and optimizer via command:

flatpak install flathub org.flozz.yoga-image-optimizer

(Optional) For any reason, you can easily remove the software by running command in temrinal:

flatpak uninstall --delete-data org.flozz.yoga-image-optimizer

2. Install the package via pip3:

For those don’t like the Flatpak package, use the Python pip3 package installer. It however does NOT create app shortcut for launching it from the ‘Show Applications’ start menu.

a.) Firstly, open terminal and run command to install required libraries:

sudo apt install git build-essential python3 python3-dev python3-pip libgirepository1.0-dev libcairo2-dev pkg-config gir1.2-gtk-3.0

b.) Next install the package via command:

sudo pip3 install yoga-image-optimizer

The pip package does not has app shortcut, you need to either run yoga-image-optimizer command to start it from terminal and create a .desktop file manually.

(Optional) To remove the package, use command:

sudo pip3 install yoga-image-optimizer
In App Review
 

How to Install GIMP 2.99.18 (GIMP 3.0 Dev) via PPA in Ubuntu 20.04

Last updated: April 7, 2024

For those don’t like the Flatpak package, here’s how to install GIMP 2.99.18 from PPA in Ubuntu 20.04 and/or Ubuntu 22.04 LTS.

The popular GIMP image editor is working on the next major 3.0 release. For testing purpose, GIMP 2.99.18 was released as the latest development version. It provides the official Linux package via Flatpak package. However, some users don’t like it, since Flatpak is an universal package format needs separate daemon to run in sandbox.

Install GIMP 3.0 Dev from PPA in Ubuntu 20.04/22.04:

For Ubuntu 20.04, Ubuntu 22.04, and derivatives, e.g, Linux Mint 20/21 and Zorin OS 17, the unofficial PPA contains the classic .deb package for GIMP 3.0 Dev release.

NOTE: The package in the PPA is unstable. It may have bugs and used only for testing purpose. Installing GIMP from this PPA will override the 2.10 stable release, don’t install it on production machine.

1. Add the PPA.

Press Ctrl+Alt+T on keyboard to open terminal, or search for and open terminal from start menu if you’re on Linux Mint or ZorinOS.

When terminal opens, copy and paste the command below and hit Run to add the PPA:

sudo add-apt-repository ppa:mati75/gimp30

Type your password as sudo command need user authentication, and hit Enter to continue.

2. Update package cache

Since Ubuntu 20.04, it updates the system package cache automatically while adding Ubuntu PPAs, However, Linux Mint 20 does not. So you may need to manually run command in terminal to update cache:

sudo apt update

3. Install / Upgrade to GIMP 3.0 Dev

Finally, you can either open Software Updater (Update Manager) to install or upgrade the GIMP package, or run command in terminal instead:

sudo apt install gimp gegl

Revert to GIMP 2.10 Stable:

It’s possible to downgrade the image editor back to 2.10 stable release, 2.10.18 if no other relevant PPA added.

Simply open terminal and run the command below to install the ppa-purge package, and then purge the Ubuntu PPA which will remove it as well as downgrade installed packages:

sudo apt install ppa-purge && sudo ppa-purge ppa:mati75/gimp30

That’s all. Enjoy!

In Howtos