RobTheFiveNine

Fix Missing Tray Icon in Signal Desktop for Linux

As of September, 2021, the Signal desktop application does not currently expose a setting in the GUI to minimise the application to the system tray. However, this functionality is available via the CLI arguments as can be seen documented in This Thread and This One.

It does seem to have been added in the beta build as per This Post:

We’ve added “official” system tray support to the latest beta! Please give it a try and report bugs here on GitHub or on the community forum.

If you’re not already on the beta, you can install it side-by-side with the production version. Click here for instructions on how to get started with the beta.

Some details about this feature:

  • It is available for Windows and Linux. Go to Signal’s settings to enable “minimize to system tray” or “start minimized to tray”.
  • These settings are off by default. We may enable them by default in the future, but have no immediate plans to do so.
  • If everything goes smoothly in beta (i.e., no significant bugs), we’ll release it to production Windows users in our next production version.
  • Because Linux system tray support is quirkier, it will stay in beta for a little while before we make it available to all users—we want to make sure it works well for most people. I don’t have an ETA for when production Linux users will get system tray support.
  • The --use-tray-icon and --start-in-tray command line arguments will continue to work on all 3 platforms. These CLI flags take precedence over settings you choose in the UI. It’s possible we’ll remove these command line arguments in the future, but we have no plans to do so, as it doesn’t significantly increase our maintenance burden.

For posterity, we added system tray support in af1f2ea and 8b30fc1.

In the meantime, if you don’t want to upgrade to using the beta build, you can add the required CLI arguments by updating the Exec property in /usr/share/applications/signal-desktop.desktop to include --use-tray-icon.

One caveat when doing this, is that updates to Signal appear to revert this change. One way of working around this (albeit a slightly hacky way), is to make use of the cron.hourly tasks.

Create a file in /etc/cron.hourly named fix-signal-taskbar with the following content:

#!/bin/sh

sed -i 's/signal-desktop --no-sandbox %U/signal-desktop --use-tray-icon --no-sandbox %U/g' /usr/share/applications/signal-desktop.desktop

Then, run chmod +x /etc/cron.hourly/fix-signal-taskbar to ensure it is executable.

You can then verify that the script will be executed by using run-parts. Running the command run-parts --test /etc/cron.hourly should list all the scripts that will be executed hourly; included in that should be /etc/cron.hourly/fix-signal-taskbar.

Alternatively, if you are using a Debian based distro that uses apt, you can instead use the Post-Invoke hook to run the command whenever apt upgrade is executed instead. To do this, create the file /etc/apt/apt.conf.d/100-fix-signal-taskbar and add the following content into it:

DPkg::Post-Invoke {"sed -i 's/signal-desktop --no-sandbox %U/signal-desktop --use-tray-icon --no-sandbox %U/g' /usr/share/applications/signal-desktop.desktop";};

As can be seen in the sample output below, when apt upgrade is executed, it will automatically patch the desktop file:

desktop :: ~ % cat /usr/share/applications/signal-desktop.desktop
[Desktop Entry]
Name=Signal
Exec=/opt/Signal/signal-desktop --no-sandbox %U
Terminal=false
Type=Application
Icon=signal-desktop
StartupWMClass=Signal
Comment=Private messaging from your desktop
MimeType=x-scheme-handler/sgnl;x-scheme-handler/signalcaptcha;
Categories=Network;InstantMessaging;Chat;

desktop :: ~ % sudo apt upgrade
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Calculating upgrade... Done
The following packages will be upgraded:
  signal-desktop
1 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
Need to get 0 B/111 MB of archives.
After this operation, 152 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
(Reading database ... 234960 files and directories currently installed.)
Preparing to unpack .../signal-desktop_6.18.1_amd64.deb ...
Unpacking signal-desktop (6.18.1) over (6.18.0) ...
Setting up signal-desktop (6.18.1) ...
Processing triggers for desktop-file-utils (0.26-1ubuntu5) ...
Processing triggers for hicolor-icon-theme (0.17-2) ...
Processing triggers for mailcap (3.70+nmu1ubuntu1) ...

desktop :: ~ % cat /usr/share/applications/signal-desktop.desktop
[Desktop Entry]
Name=Signal
Exec=/opt/Signal/signal-desktop --use-tray-icon --no-sandbox %U
Terminal=false
Type=Application
Icon=signal-desktop
StartupWMClass=Signal
Comment=Private messaging from your desktop
MimeType=x-scheme-handler/sgnl;x-scheme-handler/signalcaptcha;
Categories=Network;InstantMessaging;Chat;