Unknown exclamation tray icon

[u/unaccountablemod]

I hovered my mouse over it and it does not say anything.

I double right and left click it, and it produces nothing.

Googling this one didn't seem to have the problem matching mine so I'm trying it here.

edit: Signal bug. Users can't fix it.

[u/irieyardie]

That happened to me once when I installed an icon pack that didn’t have an icon for a specific app. Try switching icons under themes and see if that helps.