Sebastien, according to the NotifyOSD wiki merging requires the "x-canonical-append" hint. I'm not sure, but this looks like something specific to Ubuntu.
https://wiki.ubuntu.com/NotifyOSD#Treatment%20of%20the%20Desktop%20Notifications%20Specification%201.1
Sebastien, according to the NotifyOSD wiki merging requires the "x-canonical- append" hint.
I'm not sure, but this looks like something specific to Ubuntu.
https:/ /wiki.ubuntu. com/NotifyOSD# Treatment% 20of%20the% 20Desktop% 20Notifications %20Specificatio n%201.1