Thank-you Thank-you Thank-you for sharing that observation!!!
We've been having this reported by a few SmartTiles over the past few days (and I've observed it sometimes in my own tests, but @625alex and @slagle just thought I was crazy...).
OK... Just kidding about that last part. @slagle's been helpful but we haven't pinned down a reproducible case.
Until your post, I feared this was only a SmartTiles problem (we made unavoidable minor changes this week), but figured something non-SmartTiles specific must (also?) be going on... And I think there is... Right? Tell me I'm not crazy!