Slack snap - No windows, only icon in tray

Hi,

I use the Slack snap on three computers with bunsenlabs (Debian derivate with Openbox window manager and tint2 panel).

Since Slack 3.3.4 (Rev 10) I have the problem, that the windows with the workspaces are not shown.

The snap starts normally, the icon in the dock appears, but there are no windows with the workspaces. I also cannot open the workspaces using the entries in the tray icon.

After starting the snap, eight slack processes are running:

/snap/slack/10/usr/lib/slack/slack --executed-from=/home/thosch --pid=xxxx
/snap/slack/10/usr/lib/slack/slack --type=zygote --no-sandbox
/snap/slack/10/usr/lib/slack/slack --type=gpu-process --no-sandbox --gpu-preferences=xxxxx [line shortened]
/snap/slack/10/usr/lib/slack/slack --type=renderer  [line shortened]
/snap/slack/10/usr/lib/slack/slack --type=renderer  [line shortened]
/snap/slack/10/usr/lib/slack/slack --type=renderer  [line shortened]
/snap/slack/10/usr/lib/slack/slack --type=renderer  [line shortened]
/snap/slack/10/usr/lib/slack/slack --type=renderer  [line shortened]

There is only one message in /var/log/syslog

Jan 20 14:14:29 wiz /snap/bin/slack[2147]: cmd.go:105: DEBUG: restarting into "/snap/core/current/usr/bin/snap"

What going wrong here?

Regards

Thomas