Arguments against:

• I think maybe zero or one other users have ever asked for this feature, so we might be building this feature for approximately one user.
• We generally put a pretty high barrier on new options/settings (see T8227).
• This is probably at least somewhat covered by T5791 / T10448 and related work might eventually make it at least partially redundant, although I'd expect those to offer a way to drop notifications completely, not just the popup part.

Somewhat related:

• T6162 asks for "email + unread notification", which is sort of the opposite of this but if we have 5 states anyway we might as well have 6.
• T8883 is more closely related, and asks for a way to disable page notifications if desktop notifications are enabled.

Arguments for:

• This has low inherent peril and is basically a reasonable sort of request.
• With T8883, this would fit well into the "Desktop Notifications" panel: No Notifications, Desktop Only, Page Only, Page and Desktop.

More arguments against:

• I think having multiple options which enable Desktop notifications might be a gigantic pain because of the way notification permissions work?
• I think the "Desktop Notifications" panel may be way overdue for modernization?

I'm not going to jump on this right away, but my current inclination is:

• Implement this and T8883 if the "Desktop Notifications" panel is in reasonable shape.
• Wait, then implement them in the future if it isn't.

A final idle thought is that maybe the user actually wants "mute notifications on this page" or "quiet mode", in which case this is closer to T7575 / T7004 and might possibly be better covered elsewhere, but since the request is so rare I suspect we wouldn't necessarily want to conflate "published availability" with "notification behavior" or surface this in the presumably-more-prominent availability status UI we might build. I'm also not really sure we're ever going to build the T7004 version of that stuff since I'm deeply suspicious of the feature.

We've also had a request for this (disabling the in-application popups) at #dropbox, as a per-user preference.

+1, we've also had a handful of users request this as a per-user preference.

What if they're on the page, is that notification annoying? I love click that little guy.