From Cloud icon in LrC, Start Syncing. It immediately shows Synced, no change in storage used, still 415 MB. No errors appear. Photos from these two collections now appear in All Synced Photos in LrC Library Module, as expected and each has a badge showing double-arrow.
So, what am I missing? All online posts I found refer to errors, stuck sync, etc. but I don't have those symptoms.
By @GinJeff
I don't think you're missing anything, and in your description you mentioned key points that I would expect. I'd just check that you don't have more than one Adobe account, and might be logged into one in LrC, the other in the other environments. But that's a long shot, as would be a suggestion to delete via Finder rather than rebuild the sync data.
As you may have read, 13.3 uses a new syncing mechanism. The green/blue cloud icon seems less reliable, going green after syncing a few photos and then changing to blue when it does another batch. Eventually it completes, but it sounds like you're already giving it plenty of time.
What happens when you add a photo directly to LrW by dragging and dropping into the browser window, or shoot something new in LrM? Does it appear in LrC?
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