Linux – How to disable the Slack minipanel

kdocker ... it also does not appear to be able to iconify a window when closed (it actually closed instead).

As far as I understand no docker can do that. This has to be supported by the application (e.g. claws, vlc, etc). When you click on close the window manager signals the application to close, depending on its setup it closes or minimises to tray.

What I want to iconify is xfce4-terminal, so any terminal which can iconify itself and works with xfce would be ok as a solution, too.

I don't have an exact solution to this, but in terms of how it appears in window or Alt-Tab lists its identical. You could use a drop down terminal like guake. It lets you define a hotkey that will make the terminal appear and disappear. You can also add some window events as triggers for it to disappear (e.g. some other window raises itself). You can also configure other how and where it appears, what size it has. I like the fact that the terminal is always at the same place no matter when I call it and its always running at login.

The only missing feature I have found is, I can't control which display it appears on for dual display setups; it always uses the left most display.

I don't seem to have the setting that Shawn mentions, but i was able to make this work by opening up the /usr/lib/slack/resources/app.asar.unpacked/src/static directory, making a copy of the slack-taskbar-rest.png file and renaming it to slack-taskbar-unread.png to overwrite the version with the blue dot.

of course, that gets rid of the blue dot for all teams, but that's what i wanted.

Edit (2019-05-28): Idea is still correct, but for the newest Slack version (3.4.2) on Ubuntu, two more files have to be replaced. The following worked for me:

cd /usr/lib/slack/resources/app.asar.unpacked/src/static
sudo cp slack-taskbar-rest.ico slack-taskbar-unread.ico
sudo cp slack-taskbar-rest.png slack-taskbar-unread.png
sudo cp slack-taskbar-rest-linux.png slack-taskbar-unread-linux.png