Tips and Tricks

Hidding the default browser (Firefox)

If you’re using another browser than the one installed by default (Firefox) then you can hide the default one from the interface via the following commands:

$ sudo mkdir -p /usr/local/share/applications/
$ sudo cp /usr/share/applications/firefox.desktop /usr/local/share/applications/
$ sudo sed -i "2a\\NotShowIn=GNOME;KDE" /usr/local/share/applications/firefox.desktop
$ sudo update-desktop-database /usr/local/share/applications/

Enabling RPM Fusion repos

This section discusses third-party software sources not officially affiliated with or endorsed by the Fedora Project. Use them at your own discretion. Fedora recommends the use of free and open source software and avoidance of software encumbered by patents.

Users may want to take advantage of the non-free software that is made available via the RPM Fusion repos in order to use the proprietary NVIDIA drivers, multimedia codecs, or other software not distributed as part of Fedora.

The first time you install the RPM Fusion repos, you need to install the versioned RPMs:

$ sudo rpm-ostree install \
    https://mirrors.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm \
    https://mirrors.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm
$ reboot

Once you have rebooted into the new deployment, you can run the following command to remove the “lock” on the versioned packages that were installed previously. This will enable the RPM Fusion repos to be automatically updated and versioned correctly across major Fedora version rebases:

$ sudo rpm-ostree update \
    --uninstall rpmfusion-free-release \
    --uninstall rpmfusion-nonfree-release \
    --install rpmfusion-free-release \
    --install rpmfusion-nonfree-release
$ reboot

For more information, see this thread on the Fedora Discourse site.

Working with Toolbx

Finding out if you are currently in a Toolbx container

If you frequently make use of Toolbx to perform various tasks and use multiple Toolbx containers it can be hard to keep track of whether you are currently executing commands on the host or in a Toolbx container. Furthermore, there is currently no command to tell you in which Toolbx container you are working.

To alleviate this, you can add the following shell alias at the end of your ~/.bashrc:

alias istoolbx='[ -f "/run/.toolboxenv" ] && grep -oP "(?<=name=\")[^\";]+" /run/.containerenv'

When you open a new shell, you now have access to the new command istoolbx. This will behave as follows:

  • When run from the host, returns an exit code of 1

  • When run from a Toolbx container, returns an exit code of 0 and prints the current Toolbx containers name to the console

If a more automated solution is your preference the following added to your ~/.bashrc will change your bash prompt to include "[toolbox <name>]":

function is_toolbox() {
    if [ -f "/run/.toolboxenv" ]
    then
        TOOLBOX_NAME=$(cat /run/.containerenv | grep -oP "(?<=name=\")[^\";]+")
        echo "[${HOSTNAME} ${TOOLBOX_NAME}]"
    fi
}

Now you can include is_toolbox in your PS1 variable and not need to execute any extra commands in order to know whether or not your are in a toolbox or host shell.

Example:

export PS1="\[\e[31m\]\`is_toolbox\`\]\e[m\]\[\e[32m\]\\$ \[\e[m\]\[\e[37m\]❱\[\e[m\] "

This results in a prompt which appears as such when not in a toolbox: $ ❱

However, when running in a toolbox named "default" looks like: [toolbox default]$ ❱

Running applications from inside Toolbx on the host

This can be necessary if you want to interact with tools available from the host, for example podman, nmcli or rpm-ostree without leaving the Toolbx container in between. You can use flatpak-spawn, included in the base installation for this:

$ flatpak-spawn --host podman --help

If the application you want to call requires sudo access, the -S option must be supplied to sudo like below:

$ flatpak-spawn --host sudo -S rpm-ostree status

If you find yourself using commands like these frequently to access e.g. the flatpak command from inside the Toolbx container, you can create yourself a short custom wrapper script (inside the Toolbx container). To do this, perform the following steps:

  1. Define the istoolbx alias (for convenience) by executing the command mentioned above in your terminal

  2. Make sure you are in a Toolbx container. If the following command doesn’t produce any output, you are likely still working on the host!

    [toolbx]$ istoolbx
    <Toolbx container name here>
  3. Once you have made sure you’re in a Toolbx container, execute the following command:

    [toolbx]$ echo -e '#!/bin/sh\nexec /usr/bin/flatpak-spawn --host flatpak "$@"' | sudo tee /usr/local/bin/flatpak 1>/dev/null && sudo chmod +x /usr/local/bin/flatpak

You now have a flatpak command available that allows you to interact with flatpak as if you were running the command on the host.

Working with ostree/rpm-ostree

Tracking changes to the base OS

Some directories in ostree-based operating systems are writable by the user, like /etc. You can get a quick overview of the files changed under /etc using the following command:

$ sudo ostree admin config-diff

To get a more elaborate diff, you can use something like this:

$ sudo diff -yrW200 --suppress-common-lines --color=always /usr/etc /etc 2>/dev/null
This works because ostree keeps an unmodified copy of the /etc directory under /usr/etc. All of your changes go to /etc directly.

Working with Flatpak applications

Directly accessing Flatpak applications from the CLI

The most noticable change when using Flatpak applications instead of conventional installations is that the applications cannot be directly called from the CLI any more, like so:

$ evince
bash: command not found: evince

Instead, one can call them like this:

$ flatpak run org.gnome.Evince

In addition, most Flatpak applications export their internal binaries under an installation-dependent location:

  • For Flatpak applications installed from system remotes, these can be found under /var/lib/flatpak/exports/bin/

  • For Flatpak applications installed from user remotes, these can be found under $HOME/.local/share/flatpak/exports/bin/

If you’re unsure to which installation a Flatpak application belongs, you can use this command to print it out:

$ flatpak list --app --columns=name,installation

You can then either add these directories to your $PATH:

$ org.gnome.Evince

or setup shell `alias`es as needed to make them available to the CLI like so:

$ alias evince="flatpak run org.gnome.Evince"
  # or alias evince="org.gnome.Evince"
$ evince