Slack showing X11 or Wayland fallback logo in window decorations under KDE

[rushsteve1]

The Window and Status icons are missing. It shows the default fallback icons instead of the Slack icon.

Distro: Manjaro (though I have seen it on others)
DE: KDE Plasma 5.11

[nedrichards]

What version of flatpak are you using? (the output of flatpak --version in the terminal).

[rushsteve1]

Flatpak 0.10.3
Also I have just noticed that sometimes (seemingly arbitrarily) when I launch Slack the status icon is the correct Slack logo.

[nedrichards]

This sounds like a very similar issue to this one in Riot, which is also an Electron app. flathub/im.riot.Riot#3

[barthalion]

Yes, looks to be the same issue, as I haven't encountered it under GNOME on Arch.

[nedrichards]

This also may be fixed by 3.1 just released now (according to their upstream release notes) worth testing again.

[snj33v]

its not fixed

[Knusper]

Same issue here, experienced under KDE. The icon I am seeing in my panel is exactly the same as referenced in flathub/im.riot.Riot#3

[snj33v]

icons showing properly when using kde

[Knusper]

Yes - the icon shows now in KDE, but it seems a lower resolution version than when installing the slack RPM from the website.

[liposo]

Same issue in Flatpak 1.0.2 on CentOS 7 using GNOME version 3.28.2

[dac73]

On xfce it's the same problem, both task switching and task manager icons are fallback.
Status panel icon is fine.
Flatpak 1.2.4
Slack 3.3.8
Xfce 4.12

[FakeShemp]

Is this still a problem with the latest update? I tried to solve it.

[dac73]

Nope, the only thing that fixes it on Xfce is a script which I run after Slack is running

#!/bin/bash
ICON=~/.local/share/flatpak/app/com.slack.Slack/current/active/export/share/icons/hicolor/512x512/apps/com.slack.Slack.png

WINDOWS=(`wmctrl -l | grep "Slack - " | cut -f1 -d' ' | xargs`)
for slack_window in ${WINDOWS[@]}; do
    # Use "xseticon", a compiled C binary, to change the icon of a running program
    /home/dario/bin/xseticon-0.1+bzr14/xseticon -id ${slack_window} $ICON

    # Use "xprop" to set the window state, so that alt+tab works again
    xprop -f _NET_WM_WINDOW_TYPE 32a -set _NET_WM_WINDOW_TYPE _NET_WM_WINDOW_TYPE_NORMAL -id ${slack_window}
done

[FakeShemp]

How about now?

[dac73]

Same.
I don't think you can fix it here, .rpm version has the same problem on xfce (tested it). Also "script" for fixing was proposed by Slack team. They are aware of some problems, not sure if they are fixing it though :))

[FakeShemp]

Yes, it seems that is the case. Thank you very much for testing it, though. Hopefully we will see a fix some time.

[FakeShemp]

Upstream mentioned a similar fix for Cinnamon in the 4.0 update. Perhaps it works without workarounds now?

[gone]

I'm seeing this with mate

[pzkpfwVI]

I have the same issue on debian 10.4

[Knusper]

Here I am also on debian 10.4, but in KDE, and the icon shows very nicely... also the high resolution version!

[Maltimore]

@Knusper for me it also shows the correct icon in the task bar, but when I switch windows with alt-tab, the icon for Slack (and other electron apps) is the generic "X" of the X Desktop. Is it the case for you as well? (I'm also on KDE)

[tored]

Missing icon for Ubuntu MATE 20.10

alt-tab: fallbacks Ubuntu MATE's icon for Appearance app.
taskbar: some default icon looking like a empty window

My guess, without knowing much about flatpaks and .desktop-files, is this Slack flatpak only ships with a 512x512 icon in this folder

/var/lib/flatpak/app/com.slack.Slack/current/active/export/share/icons/hicolor

Probably 512x512 is just too big in many cases.

If I compare that with the Bitwarden flatpak, that works for me, is has multiple icon sizes

/var/lib/flatpak/app/com.bitwarden.desktop/current/active/export/share/icons/hicolor

128x128 16x16 256x256 32x32 48x48 512x512 64x64

[dylanmtaylor]

I am also missing the icon on a machine running the MATE desktop with Flatpak version 1.0.9.

[jmayday]

➜  ~ flatpak --version
Flatpak 1.12.4
➜  ~ flatpak list  
Name                       Application ID                              Version    Branch       Installation
teams-for-linux            com.github.IsmaelMartinez.teams_for_linux   1.0.24     stable       system
Slack                      com.slack.Slack                             4.26.1     stable       system
Freedesktop Platform       org.freedesktop.Platform                    21.08.14   21.08        system
Mesa                       org.freedesktop.Platform.GL.default         21.3.8     21.08        system
Intel                      org.freedesktop.Platform.VAAPI.Intel                   21.08        system
openh264                   org.freedesktop.Platform.openh264           2.1.0      2.0          system
Breeze GTK theme           org.gtk.Gtk3theme.Breeze                    5.25.0     3.22         system
KDE Application Platform   org.kde.Platform                                       5.15-21.08   system
VLC                        org.videolan.VLC                            3.0.17.4   stable       system
➜  ~ 
➜  ~ cat /etc/os-release 
NAME="KDE neon"
VERSION="5.25"
ID=neon
ID_LIKE="ubuntu debian"
PRETTY_NAME="KDE neon User - 5.25"
VARIANT="User Edition"
VARIANT_ID=user
VERSION_ID="20.04"
HOME_URL="https://neon.kde.org/"
SUPPORT_URL="https://neon.kde.org/"
BUG_REPORT_URL="https://bugs.kde.org/"
LOGO=start-here-kde-neon
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal

[grongor]

I just installed it on Fedora; the icon in the taskbar is correct, but the one in the task switcher and "top left corner" is still the X.

[aardk]

Same issue (missing icon in taskbar) under Fedora38 KDE, solved by copying an svg icon for Slack to /var/lib/flatpak/exports/share/icons/hicolor/scalable/apps/

Note that the name of the icon should be com.slack.Slack.svg

[ZVNexus]

To fix this we need Slack to start reporting their app ID as "com.slack.Slack" (unlikely to happen), or for KWin to workaround the issue similar to how they do it for taskbar.

[afiestas]

A workaround is to force the desktop file to com.slack.Slack with a window rule

[ryaminal]

@afiestas, thank you for sharing that! definitely worked. had to restart the app(not certain if that's necessary) and it worked!

curious if anyone knows a CLI equivalent for this? with a kwin script or something? but be nice to share as this is probably a common workaround.

[Maltimore]

Are you already on KDE Plasma 6.0? Because it is fixed for me now, without me doing anything. I'm not 100% sure though that this came with the switch to Plasma 6.
Edit: I'm on X11 on Plasma 6. Just adding this info so you know it wasn't fixed by switching to wayland.

[ryaminal]

@Maltimore, this was a fresh install of Fedora Atomic Kinoite with Plasma 6.0.3 that i still had to add the workaround.