Correct. Notification bar shows only one. As does the notification module in Lucid Daydream, which is what I'm using to force klwp to be visible in sleep mode.
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Ahh, I see what's going on now. In further testing, it seems Google Inbox is trying to be helpful...
I added additional text fields to each line in my notification object
$ni(X, app)$ - $ni(X, text)$
to see what message was doing what. Turns out, the first notification from Inbox tells us the mailbox that's active, followed then by the first actual message notification. Second notification and beyond show the subject lines of each message as expected.
Looks like I'll need additional code to parse out which notifications I actually want. Time to start searching for examples!
Thanks, Frank, for all your hard work on this app. The more I dive into it, the more I learn, and the more I enjoy it.