I've installed the Slack snap; recently, its tray icon stopped displaying. Instead there's just a blank space – though if I right-click it, the Slack menu still opens. All my other tray icons are working fine.
Why has Slack's icon disappeared, and how can I get it back?
I'm using i3 with i3bar to display tray icons, on Ubuntu 18.04. Slack is currently at version 3.3.7.
It's a problem present since months in the Snap version of Slack. One possible workaround is using the DEB version, the other is restarting the system until it works. Usually, the latter does not work.