Option to persist notifications

[joshuamegnauth54]

macOS supports persisting notifications until dismissed. This is useful to keep important notifications around instead of having them time out. Currently, this applies to all apps but it composes well with per-app notification settings (which is a future feature, most likely).

See: pop-os/cosmic-settings#1878

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This feature was requested in the linked PR. I'll likely implement per-app settings then move this setting over to that to match macOS. However, this works as intended for now. The easiest way to test it is to use send-notify.

To enable persistence, write true to the persistence settings file.

echo true > ~/.config/cosmic/com.system76.CosmicNotifications/v1/persistence

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[hojjatabdollahi]

I suggest this config to be similar to the one I created in #158 . Instead of a boolean, the user can choose None/All/Urgent only. I don't want All my notifications to persist, that's annoying, but I do like to keep the urgent ones around until I dismiss them.

[wash2]

I suggest this config to be similar to the one I created in #158 . Instead of a boolean, the user can choose None/All/Urgent only. I don't want All my notifications to persist, that's annoying, but I do like to keep the urgent ones around until I dismiss them.

That's a great point!

[joshuamegnauth54]

Sure! 😁 That's a great idea. I'll wait till your patch is merged, and then I'll rebase mine so I could reuse/rename your FullscreenBehavior type.