Ticket "disappears" after updating a ticket

Infos:

  • Used Zammad version: 5.2.1
  • Used Zammad installation type: package (apt)
  • Operating system: Ubuntu 16.04
  • Browser + version: Chrome / Vivaldi / Edge latest versions

Intro:

I have a very peculiar problem, which I can not really understand.

The problem affects only one agent and is browser independent.
For the one agent, the updated ticket disappears from the taskbar and it “minimizes” when he presses the “update” button. First I thought it may be a trigger or something like that, but I only use 5 triggers and none of them can cause this.
I had a look in the production log, but I didn’t find anything.
Here is a video to demonstrate what I mean.
I took over the session of the agent to show that it is probably not a problem with the browser or similar.

Expected behavior:

  • ticket stays in the taskbar

Actual behavior:

  • ticket disappears from the taskbar

Steps to reproduce the behavior:

  • I don’t think it’s reproducable, as it only affects one single agent in the whole system…

What I tried so far:

deactivate and reactivate the user

zammad run rails r "Cache.clear"
zammad restart

https://user-docs.zammad.org/en/latest/advanced/tabs.html#tab-behavior-in-ticket-zooms