Permanent firefox notification badge?

gnome linux dock: why does firefox have a (1) badge and how do I get rid of it?

Closing all tabs? Nope. Quitting and restarting? Nope. Opening Downloads list? No. Gnome notification settings? No.

Ahhh - Gnome message tray, Meta-M: there was a “tab arrived from other device” notification. Clear that: no more badge.

Solving this took 15 minutes of LLM interrogation. Before that was a week of daily irritation and unsuccessful web searches. It really is the little things that make and break experience, that determine quality of mind and attention.