Running applications do not appear in the taskbar

[FrenchPress]

@zabadabadoo
I saw someone is asking a similar question in another new thread:

Program-icons disappear, while program still runs

Hello everyone! I've been using ZorinOS 16 for a while now and very happy with it! But I have 1 problem... [Icons dissapear] A few apps icons disappear in the taskbar over time. Like, for example, CopyQ is often gone and therefore no longer useful for me. In the task manager, the app is still there, so starting from the menu doesn't help. I have to close the app in the task manager first and then restart it to have the icon back... And then be gone again later. Chrome icon disappears when I …

Do you think I should merge that question here?
Or do you think it is a separate issue?